diff --git a/python/eckit/src/_eckit/_eckit_geo.pyx b/python/eckit/src/_eckit/_eckit_geo.pyx
index 7637a6f5d..4d6749f2b 100644
--- a/python/eckit/src/_eckit/_eckit_geo.pyx
+++ b/python/eckit/src/_eckit/_eckit_geo.pyx
@@ -10,6 +10,8 @@
 
 cimport eckit_geo
 from cython.operator cimport dereference
+from libcpp.memory cimport unique_ptr
+from libcpp.string cimport string
 from libcpp.utility cimport pair
 from libcpp.vector cimport vector
 
@@ -30,6 +32,22 @@ def cache_dir_purge() -> None:
     eckit_geo.LibEcKitGeo.purgeCacheDir()
 
 
+def ensure_proj_database(fallback_db, fallback_search_paths=()) -> bool:
+    """Ensure eckit's PROJ subsystem can find a usable proj.db.
+
+    Respects PROJ_DATA/PROJ_LIB and any database PROJ can already resolve on
+    its own; only if neither yields a database does it fall back to the given
+    proj.db + search paths. No-op (returns False) when eckit was built without
+    PROJ. See LibEcKitGeo::ensureProjDatabase for the full policy.
+    """
+    cdef vector[string] paths
+    cdef string db
+    for p in fallback_search_paths:
+        paths.push_back(p.encode("utf-8") if isinstance(p, str) else p)
+    db = fallback_db.encode("utf-8") if isinstance(fallback_db, str) else fallback_db
+    return eckit_geo.LibEcKitGeo.ensureProjDatabase(db, paths)
+
+
 cdef class Area:
     cdef const eckit_geo.Area* _area
 
@@ -72,6 +90,170 @@ cdef class Area:
         return self._area.type()
 
 
+cdef class BoundingBox:
+    cdef eckit_geo.BoundingBox* _bbox
+
+    def __dealloc__(self):
+        if self._bbox != NULL:
+            del self._bbox
+
+    def __cinit__(self, north=None, west=None, south=None, east=None):
+        self._bbox = NULL
+
+        cdef unique_ptr[eckit_geo.BoundingBox] bbox
+        bbox = eckit_geo.BoundingBox.make_from_area(
+            float(north), float(west), float(south), float(east),
+        )
+        self._bbox = bbox.release()
+
+    def intersects(self, other) -> bool:
+        cdef BoundingBox other_bbox
+        cdef bint intersects
+        if not isinstance(other, BoundingBox):
+            raise TypeError("other must be a BoundingBox")
+        other_bbox = <BoundingBox>other
+        intersects = eckit_geo.bbox_intersects(
+            dereference(self._bbox), dereference(other_bbox._bbox)
+        )
+        return intersects
+
+    def contains(self, other) -> bool:
+        cdef BoundingBox other_bbox
+        if not isinstance(other, BoundingBox):
+            raise TypeError("other must be a BoundingBox")
+        other_bbox = <BoundingBox>other
+        return self._bbox.contains(dereference(other_bbox._bbox))
+
+    def contains_point(self, lon, lat) -> bool:
+        return eckit_geo.bbox_contains_lonlat(
+            dereference(self._bbox), float(lon), float(lat)
+        )
+
+    def as_list(self) -> list:
+        return [self.north, self.west, self.south, self.east]
+
+    @property
+    def spec_str(self) -> str:
+        return self._bbox.spec_str()
+
+    @property
+    def spec(self) -> dict:
+        from yaml import safe_load
+        return safe_load(self.spec_str)
+
+    @property
+    def north(self) -> float:
+        return self._bbox.north()
+
+    @property
+    def west(self) -> float:
+        return self._bbox.west()
+
+    @property
+    def south(self) -> float:
+        return self._bbox.south()
+
+    @property
+    def east(self) -> float:
+        return self._bbox.east()
+
+    @property
+    def global_(self) -> bool:
+        return self._bbox.is_global()
+
+    @property
+    def periodic(self) -> bool:
+        return self._bbox.periodic()
+
+    @property
+    def empty(self) -> bool:
+        return self._bbox.empty()
+
+    @property
+    def area(self) -> float:
+        return self._bbox.area()
+
+    def __repr__(self) -> str:
+        return str(self.as_list())
+
+    __str__ = __repr__
+
+
+cdef class Figure:
+    cdef const eckit_geo.Figure* _figure
+
+    def __dealloc__(self):
+        if self._figure != NULL:
+            del self._figure
+
+    def __cinit__(self, spec = None, **kwargs):
+        self._figure = NULL
+        assert bool(spec) != bool(kwargs)
+
+        if kwargs or isinstance(spec, dict):
+            from yaml import dump
+            spec = dump(kwargs if kwargs else spec, default_flow_style=True).strip()
+
+        try:
+            assert isinstance(spec, str)
+            self._figure = eckit_geo.FigureFactory.make_from_string(spec)
+
+        except RuntimeError as e:
+            # opportunity to do something interesting
+            raise
+
+    def __eq__(self, other) -> bool:
+        if not isinstance(other, Figure):
+            return NotImplemented
+        return self.spec_str == other.spec_str
+
+    def area(self, bbox = None) -> float:
+        cdef BoundingBox _bbox
+        if bbox is None:
+            return self._figure.area()
+        if not isinstance(bbox, BoundingBox):
+            raise TypeError("bbox must be a BoundingBox")
+        _bbox = <BoundingBox>bbox
+        return self._figure.area(dereference(_bbox._bbox))
+
+    @property
+    def R(self) -> float:
+        return eckit_geo.figure_R(dereference(self._figure))
+
+    @property
+    def a(self) -> float:
+        return self._figure.a()
+
+    @property
+    def b(self) -> float:
+        return self._figure.b()
+
+    @property
+    def spec_str(self) -> str:
+        return self._figure.spec_str()
+
+    @property
+    def spec(self) -> dict:
+        from yaml import safe_load
+        return safe_load(self.spec_str)
+
+    @property
+    def proj_str(self) -> str:
+        return self._figure.proj_str()
+
+    @property
+    def spherical(self) -> bool:
+        return self._figure.spherical()
+
+    @property
+    def eccentricity(self) -> float:
+        return self._figure.eccentricity()
+
+    @property
+    def flattening(self) -> float:
+        return self._figure.flattening()
+
+
 cdef class Grid:
     cdef const eckit_geo.Grid* _grid
 
diff --git a/python/eckit/src/_eckit/eckit_geo.pxd b/python/eckit/src/_eckit/eckit_geo.pxd
index 42c57706c..0028148d8 100644
--- a/python/eckit/src/_eckit/eckit_geo.pxd
+++ b/python/eckit/src/_eckit/eckit_geo.pxd
@@ -8,6 +8,8 @@
 # does it submit to any jurisdiction.
 
 
+from libcpp cimport bool
+from libcpp.memory cimport unique_ptr
 from libcpp.string cimport string
 from libcpp.utility cimport pair
 from libcpp.vector cimport vector
@@ -21,6 +23,9 @@ cdef extern from "eckit/geo/LibEcKitGeo.h" namespace "eckit":
         @staticmethod
         void purgeCacheDir()
 
+        @staticmethod
+        bool ensureProjDatabase(const string& fallback_db, const vector[string]& fallback_search_paths) except +
+
         string version()
         string gitsha1(unsigned int n)  # n=40 for full sha1
 
@@ -37,11 +42,42 @@ cdef extern from "eckit/geo/Area.h" namespace "eckit::geo":
 
 cdef extern from "eckit/geo/area/BoundingBox.h" namespace "eckit::geo::area":
     cdef cppclass BoundingBox(Area):
+        BoundingBox(double north, double west, double south, double east) except +
+
         double north() const
         double west() const
         double south() const
         double east() const
 
+        bool intersects(BoundingBox&) const
+        bool contains(const BoundingBox&) const
+        bool is_global "global"() const
+        bool periodic() const
+        bool empty() const
+        double area() const
+
+        @staticmethod
+        unique_ptr[BoundingBox] make_from_area(
+            double n, double w, double s, double e
+        ) except +
+
+
+cdef extern from "eckit/geo/Figure.h" namespace "eckit::geo":
+    cdef cppclass Figure:
+        double a() const
+        double b() const
+        double area() const
+        double area(const BoundingBox&) const
+        string spec_str() const
+        string proj_str() const
+        bool spherical() const
+        double eccentricity() const
+        double flattening() const
+
+    cdef cppclass FigureFactory:
+        @staticmethod
+        Figure* make_from_string(const string) except +
+
 
 cdef extern from "eckit/geo/Range.h" namespace "eckit::geo":
     cdef cppclass Range:
@@ -75,7 +111,10 @@ cdef extern from * namespace "eckit::geo::python":
     """
     #include <vector>
 
+    #include "eckit/geo/area/BoundingBox.h"
+    #include "eckit/geo/Figure.h"
     #include "eckit/geo/Grid.h"
+    #include "eckit/geo/PointLonLat.h"
 
     namespace eckit::geo::python {
 
@@ -86,9 +125,25 @@ cdef extern from * namespace "eckit::geo::python":
     inline v grid_lon_values(const Grid& grid) { return grid.lon().values(); }
     inline v grid_lat_values(const Grid& grid) { return grid.lat().values(); }
 
+    inline bool bbox_intersects(const area::BoundingBox& lhs, area::BoundingBox& rhs) {
+        return lhs.intersects(rhs);
+    }
+
+    inline bool bbox_contains_lonlat(
+        const area::BoundingBox& bbox, double lon, double lat
+    ) {
+        return bbox.contains(PointLonLat{lon, lat});
+    }
+
+    inline double figure_R(const Figure& figure) { return figure.R(); }
+
     }
     """
     vector[double] grid_x_values(const Grid& grid) except +
     vector[double] grid_y_values(const Grid& grid) except +
     vector[double] grid_lon_values(const Grid& grid) except +
     vector[double] grid_lat_values(const Grid& grid) except +
+
+    bint bbox_intersects(const BoundingBox& lhs, BoundingBox& rhs) except +
+    bint bbox_contains_lonlat(const BoundingBox& bbox, double lon, double lat) except +
+    double figure_R(const Figure& figure) except +
diff --git a/python/eckit/src/eckit/geo/__init__.py b/python/eckit/src/eckit/geo/__init__.py
index 067191e0d..16302cd14 100644
--- a/python/eckit/src/eckit/geo/__init__.py
+++ b/python/eckit/src/eckit/geo/__init__.py
@@ -7,12 +7,43 @@
 # granted to it by virtue of its status as an intergovernmental organisation nor
 # does it submit to any jurisdiction.
 
+from pathlib import Path
+
 import findlibs
 
 findlibs.load("eckit", "eckitlib")
 findlibs.load("eckit_maths", "eckitlib")
 findlibs.load("eckit_geo", "eckitlib")
 
+
+def _configure_eckit_proj() -> None:
+    """
+    Point eckit's PROJ to the proj.db in the eckitlib wheel, so projections work out of the box.
+
+    All the policy is in LibEcKitGeo::ensureProjDatabase. Here we only discover the candidate
+    bundled location (it knows where pip installed the eckitlib package).
+    """
+    try:
+        import eckitlib
+    except ImportError:
+        return
+    eckitlib_file = getattr(eckitlib, "__file__", None)
+    if not eckitlib_file:
+        return
+
+    proj_dir = Path(eckitlib_file).parent / "share" / "proj"
+    from eckit.geo._eckit_geo import ensure_proj_database
+
+    if not ensure_proj_database(str(proj_dir / "proj.db"), [str(proj_dir)]):
+        import warnings
+
+        warnings.warn(
+            f"Could not find bundled proj.db at {proj_dir / 'proj.db'}, projection support is limited. Please install PROJ and/or set the PROJ_DATA environment variable."
+        )
+
+
+_configure_eckit_proj()
+
 from eckit._certifi import configure_ca_bundle_from_certifi
 from eckit.geo._eckit_geo import *
 
diff --git a/python/eckit/tests/test_area.py b/python/eckit/tests/geo/test_area.py
similarity index 52%
rename from python/eckit/tests/test_area.py
rename to python/eckit/tests/geo/test_area.py
index f71d00866..a5a6e37a0 100644
--- a/python/eckit/tests/test_area.py
+++ b/python/eckit/tests/geo/test_area.py
@@ -8,20 +8,8 @@
 # does it submit to any jurisdiction.
 
 
-import pytest
-
-SPECS = [
-    (dict(north=90, west=0, south=-90, east=360), dict(area=[90, 0, -90, 360])),
-    (
-        dict(north=10, west=360 * 99 + 1, south=0, east=360 * 42 + 10),
-        dict(area=[10, 1, 0, 10]),
-    ),
-]
-
-
-@pytest.mark.parametrize("_spec, _expected", SPECS)
-def test_area(_spec, _expected):
+def test_area():
     from eckit.geo import Area
 
-    area = Area(_spec)
-    assert area.spec == _expected
+    area = Area(dict(north=90, west=0, south=-90, east=360))
+    assert area.spec == dict(area=[90, 0, -90, 360])
diff --git a/python/eckit/tests/geo/test_bbox.py b/python/eckit/tests/geo/test_bbox.py
new file mode 100644
index 000000000..409431aa6
--- /dev/null
+++ b/python/eckit/tests/geo/test_bbox.py
@@ -0,0 +1,69 @@
+# (C) Copyright 1996- ECMWF.
+#
+# This software is licensed under the terms of the Apache Licence Version 2.0
+# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+#
+# In applying this licence, ECMWF does not waive the privileges and immunities
+# granted to it by virtue of its status as an intergovernmental organisation nor
+# does it submit to any jurisdiction.
+
+
+import pytest
+
+from eckit.geo import BoundingBox
+
+SPECS = [
+    (dict(north=90, west=0, south=-90, east=360), dict(area=[90, 0, -90, 360])),
+    (
+        dict(north=10, west=360 * 99 + 1, south=0, east=360 * 42 + 10),
+        dict(area=[10, 1, 0, 10]),
+    ),
+]
+
+
+@pytest.mark.parametrize("_spec, _expected", SPECS)
+def test_bbox_spec(_spec, _expected):
+    bbox = BoundingBox(**_spec)
+    assert bbox.spec == _expected
+
+
+def test_bbox_global():
+    bbox = BoundingBox(north=90, west=0, south=-90, east=360)
+
+    assert bbox.as_list() == [90, 0, -90, 360]
+    assert bbox.global_
+    assert not bbox.empty
+    assert bbox.periodic
+
+
+def test_bbox_not_global():
+    bbox = BoundingBox(north=10, west=0, south=0, east=10)
+
+    assert not bbox.global_
+    assert not bbox.empty
+    assert not bbox.periodic
+
+
+def test_bbox_intersects_and_contains():
+    outer = BoundingBox(north=10, west=0, south=-10, east=10)
+    inner = BoundingBox(north=5, west=2, south=-5, east=8)
+    disjoint = BoundingBox(north=20, west=20, south=15, east=30)
+
+    assert outer.intersects(inner)
+    assert outer.contains(inner)
+    assert not inner.contains(outer)
+    assert not outer.intersects(disjoint)
+    assert not outer.contains(disjoint)
+
+
+def test_bbox_contains_point():
+    bbox = BoundingBox(north=10, west=0, south=-10, east=10)
+
+    assert bbox.contains_point(5, 5)
+    assert not bbox.contains_point(50, 50)
+
+
+def test_bbox_area():
+    bbox = BoundingBox(north=90, west=0, south=-90, east=360)
+
+    assert bbox.area > 0
diff --git a/python/eckit/tests/geo/test_figure.py b/python/eckit/tests/geo/test_figure.py
new file mode 100644
index 000000000..033e66615
--- /dev/null
+++ b/python/eckit/tests/geo/test_figure.py
@@ -0,0 +1,53 @@
+# (C) Copyright 1996- ECMWF.
+#
+# This software is licensed under the terms of the Apache Licence Version 2.0
+# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+#
+# In applying this licence, ECMWF does not waive the privileges and immunities
+# granted to it by virtue of its status as an intergovernmental organisation nor
+# does it submit to any jurisdiction.
+
+
+import pytest
+
+from eckit.geo import BoundingBox
+from eckit.geo import Figure
+
+
+def test_figure_earth():
+    R = 6371229.0
+    A = 510101140207791.56
+
+    figure = Figure(R=R)
+
+    assert figure.R == R
+    assert figure.a == figure.R
+    assert figure.b == figure.R
+    assert figure.spherical
+    assert figure.eccentricity == 0
+    assert figure.flattening == 0
+    assert figure.spec == dict(r=R)
+
+    assert A == pytest.approx(figure.area())
+    assert A == pytest.approx(figure.area(BoundingBox(north=90, west=0, south=-90, east=360)))
+    assert A / 2 == pytest.approx(figure.area(BoundingBox(north=90, west=0, south=0, east=360)))
+
+
+def test_figure_wgs84():
+    A = 510065621724079.0
+
+    figure = Figure(figure="wgs84")
+
+    with pytest.raises(Exception):
+        figure.R  # not defined for a != b
+
+    assert figure.a == pytest.approx(6378137.0)
+    assert figure.b == pytest.approx(6356752.314245)
+    assert not figure.spherical
+    assert 0 < figure.eccentricity < 1
+    assert figure.flattening == pytest.approx(1 - figure.b / figure.a)
+    assert figure.spec == dict(figure="wgs84")
+
+    assert A == pytest.approx(figure.area())
+    assert A == pytest.approx(figure.area(BoundingBox(north=90, west=0, south=-90, east=360)))
+    assert A / 2 == pytest.approx(figure.area(BoundingBox(north=90, west=0, south=0, east=360)))
diff --git a/python/eckit/tests/test_grid.py b/python/eckit/tests/geo/test_grid.py
similarity index 100%
rename from python/eckit/tests/test_grid.py
rename to python/eckit/tests/geo/test_grid.py
diff --git a/python/eckitlib/buildconfig b/python/eckitlib/buildconfig
index 5fa392b54..99ec516e2 100644
--- a/python/eckitlib/buildconfig
+++ b/python/eckitlib/buildconfig
@@ -13,6 +13,6 @@
 NAME="eckit"
 _HERE="$(dirname -- "$(readlink -f -- "${BASH_SOURCE[0]}")")"
 PYTHON_INSTALL_DIR=$(cd -- "$_HERE/../eckit/src" && pwd) # dont use readlink -m here, not macos portable
-CMAKE_PARAMS="-DENABLE_MPI=0  -DENABLE_ECKIT_GEO=1 -DENABLE_BUILD_TOOLS=OFF -DENABLE_AEC=0 -DENABLE_EIGEN=0 -DENABLE_LZ4=1 -DENABLE_PYTHON=1 -DPYTHONEXT_INSTALL_DIR=$PYTHON_INSTALL_DIR"
+CMAKE_PARAMS="-DENABLE_MPI=0  -DENABLE_ECKIT_GEO=1 -DENABLE_BUILD_TOOLS=OFF -DENABLE_AEC=0 -DENABLE_EIGEN=0 -DENABLE_LZ4=1 -DENABLE_PYTHON=1 -DPYTHONEXT_INSTALL_DIR=$PYTHON_INSTALL_DIR -DENABLE_PROJ=1"
 PYPROJECT_DIR="python/eckitlib"
 DEPENDENCIES='[]'
diff --git a/python/eckitlib/post-build.sh b/python/eckitlib/post-build.sh
index c66cccca8..4e001fc16 100755
--- a/python/eckitlib/post-build.sh
+++ b/python/eckitlib/post-build.sh
@@ -2,18 +2,196 @@
 
 set -euo pipefail
 
+SCRIPT_DIR=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)
+ECKIT_SRC_DIR=$(cd -- "$SCRIPT_DIR/../eckit/src" && pwd)
+
+compute_relative_up() {
+    local rel_dir="$1"
+    if [ -z "$rel_dir" ] || [ "$rel_dir" = "." ]; then
+        echo ""
+        return
+    fi
+    local count
+    count=$(echo "$rel_dir" | awk -F'/' '{print NF}')
+    local up=""
+    for ((i=0; i<count; i++)); do
+        up="../$up"
+    done
+    echo "$up"
+}
+
+extract_lib_stem() {
+    local name
+    name=$(basename "$1")
+    local stem="${name%%.so*}"
+    stem="${stem%%.dylib*}"
+    stem="${stem%%.*}"
+    stem="${stem%%-*}"
+    echo "$stem"
+}
+
+find_matching_vendor_lib() {
+    local vendor_dir="$1"
+    local needed_lib="$2"
+
+    local stem
+    stem=$(extract_lib_stem "$needed_lib")
+
+    if [ -z "$stem" ] || [ ! -d "$vendor_dir" ]; then
+        return
+    fi
+
+    local match
+    match=$(find "$vendor_dir" -maxdepth 1 \( -name "${stem}-*" -o -name "${stem}.*" -o -name "${stem}" \) | head -n 1)
+    if [ -n "$match" ]; then
+        basename "$match"
+    fi
+}
+
+process_binary_linux() {
+    local bin_file="$1"
+    local eckit_src_dir="$2"
+    local vendor_dir="$3"
+
+    local bin_dir
+    bin_dir=$(dirname "$bin_file")
+    local rel_dir="${bin_dir#"$eckit_src_dir"}"
+    rel_dir="${rel_dir#/}"
+
+    local rel_up
+    rel_up=$(compute_relative_up "$rel_dir")
+    local vendor_dir_name
+    vendor_dir_name=$(basename "$vendor_dir")
+
+    # shellcheck disable=SC2016
+    local rpath='$ORIGIN/'"${rel_up}${vendor_dir_name}:"' $ORIGIN/'"${rel_up}eckitlib"
+    # Clean up any whitespace introduced above
+    rpath=$(echo "$rpath" | tr -d ' ')
+
+    echo "running patchelf --print-needed $bin_file"
+    local needed_libs
+    needed_libs=$(patchelf --print-needed "$bin_file")
+
+    while read -r needed_lib; do
+        [ -z "$needed_lib" ] && continue
+        local matched_lib
+        matched_lib=$(find_matching_vendor_lib "$vendor_dir" "$needed_lib")
+        if [ -n "$matched_lib" ]; then
+            echo "running patchelf --replace-needed $needed_lib $matched_lib $bin_file"
+            patchelf --replace-needed "$needed_lib" "$matched_lib" "$bin_file"
+        fi
+    done <<< "$needed_libs"
+
+    echo "running patchelf --add-rpath $rpath $bin_file"
+    patchelf --add-rpath "$rpath" "$bin_file"
+}
+
+process_binary_macos() {
+    local bin_file="$1"
+    local eckit_src_dir="$2"
+    local vendor_dir="$3"
+
+    local bin_dir
+    bin_dir=$(dirname "$bin_file")
+    local rel_dir="${bin_dir#"$eckit_src_dir"}"
+    rel_dir="${rel_dir#/}"
+
+    local rel_up
+    rel_up=$(compute_relative_up "$rel_dir")
+    local vendor_dir_name
+    vendor_dir_name=$(basename "$vendor_dir")
+
+    local rpath_vendor="@loader_path/${rel_up}${vendor_dir_name}"
+    local rpath_eckit="@loader_path/${rel_up}eckitlib"
+
+    echo "running otool -L $bin_file"
+    local otool_out
+    otool_out=$(otool -L "$bin_file")
+
+    echo "$otool_out" | tail -n +2 | awk '{print $1}' | while read -r dep_path; do
+        [ -z "$dep_path" ] && continue
+        # Ignore system libraries and existing rpath/loader_path entries
+        case "$dep_path" in
+            /usr/lib/*|/System/Library/*|@rpath/*|@loader_path/*)
+                continue
+                ;;
+        esac
+
+        local matched_lib
+        matched_lib=$(find_matching_vendor_lib "$vendor_dir" "$dep_path")
+        if [ -n "$matched_lib" ]; then
+            echo "running install_name_tool -change $dep_path @rpath/$matched_lib $bin_file"
+            install_name_tool -change "$dep_path" "@rpath/$matched_lib" "$bin_file"
+        fi
+    done
+
+    echo "running install_name_tool -add_rpath $rpath_vendor $bin_file"
+    install_name_tool -add_rpath "$rpath_vendor" "$bin_file" 2>/dev/null || true
+
+    echo "running install_name_tool -add_rpath $rpath_eckit $bin_file"
+    install_name_tool -add_rpath "$rpath_eckit" "$bin_file" 2>/dev/null || true
+}
+
+fix_another_wheel_linux() {
+    local vendor_dir="$1"
+
+    echo "will crawl $ECKIT_SRC_DIR"
+    if [ -d "$ECKIT_SRC_DIR" ]; then
+        while read -r bin_file; do
+            [ -z "$bin_file" ] && continue
+            echo "found $bin_file, will process it"
+            process_binary_linux "$bin_file" "$ECKIT_SRC_DIR" "$vendor_dir"
+        done < <(find "$ECKIT_SRC_DIR" -type f -name "*.so")
+    fi
+}
+
+fix_another_wheel_macos() {
+    local wheel_file="$1"
+
+    echo "inspecting delocated wheel $wheel_file"
+    local inspect_dir="/tmp/eckit/delocate_inspect"
+    rm -rf "$inspect_dir"
+    mkdir -p "$inspect_dir"
+    unzip -q "$wheel_file" -d "$inspect_dir"
+
+    local vendor_dir
+    vendor_dir=$(find "$inspect_dir" -maxdepth 2 -type d \( -name "*.dylibs" -o -name ".dylibs" -o -name "*.libs" \) | head -n 1)
+
+    if [ -n "$vendor_dir" ] && [ -d "$vendor_dir" ]; then
+        echo "found vendor dylibs at $vendor_dir"
+    else
+        echo "warning: vendor dylibs directory not found in $wheel_file"
+        vendor_dir="$inspect_dir"
+    fi
+
+    echo "will crawl $ECKIT_SRC_DIR"
+    if [ -d "$ECKIT_SRC_DIR" ]; then
+        while read -r bin_file; do
+            [ -z "$bin_file" ] && continue
+            echo "found $bin_file, will process it"
+            process_binary_macos "$bin_file" "$ECKIT_SRC_DIR" "$vendor_dir"
+        done < <(find "$ECKIT_SRC_DIR" -type f \( -name "*.so" -o -name "*.dylib" \))
+    fi
+
+    rm -rf "$inspect_dir"
+}
+
 # NOTE in case of problems like we had with eccodes, replace with noop here
 if [ "$(uname)" != "Darwin" ] ; then
     rm -rf /tmp/eckit/auditwheel
     auditwheel repair -w /tmp/eckit/auditwheel /tmp/eckit/build/wheel/*whl
     cd /tmp/eckit/auditwheel
-    F=$(ls *whl)
-    unzip $F
+    F=$(basename "$(ls ./*.whl)")
+    unzip "$F"
+    # shellcheck disable=SC2016
     patchelf --add-rpath '$ORIGIN' eckitlib.libs/*
-    rm $F
-    zip -r $F ./*
+
+    fix_another_wheel_linux "/tmp/eckit/auditwheel/eckitlib.libs"
+
+    rm "$F"
+    zip -r "$F" ./*
     rm /tmp/eckit/build/wheel/*
-    mv /tmp/eckit/auditwheel/$F /tmp/eckit/build/wheel
+    mv "/tmp/eckit/auditwheel/$F" /tmp/eckit/build/wheel
     cd -
 fi
 
@@ -21,4 +199,8 @@ fi
 # is disabled anyway
 if [ "$(uname)" = "Darwin" ] ; then
     delocate-wheel /tmp/eckit/build/wheel/*whl
+    WHEEL_FILE=$(find /tmp/eckit/build/wheel -name "*.whl" | head -n 1)
+    if [ -n "$WHEEL_FILE" ]; then
+        fix_another_wheel_macos "$WHEEL_FILE"
+    fi
 fi
diff --git a/python/eckitlib/pre-compile.sh b/python/eckitlib/pre-compile.sh
index 08bc49497..417494455 100755
--- a/python/eckitlib/pre-compile.sh
+++ b/python/eckitlib/pre-compile.sh
@@ -14,6 +14,11 @@
 
 set -euo pipefail
 
+# Source the buildconfig so we can inspect $CMAKE_PARAMS below (e.g. to decide
+# whether to bundle PROJ's data files).
+# shellcheck source=/dev/null
+source python/eckitlib/buildconfig
+
 mkdir -p python/eckitlib/src/copying
 mkdir -p /tmp/eckit/target/eckit/lib64/
 
@@ -24,12 +29,37 @@ if [ "$(uname)" != "Darwin" ] ; then
     # git clone https://github.com/lz4/lz4 /src/lz4 && cd /src/lz4
     # make -j10 && make install DESTDIR=/tmp/lz4
     # cd -
+    PROJ_ROOT="${PROJ_ROOT:-/cxx-deps}"
 else
     echo "no deps installation for platform $(uname)"
+    PROJ_ROOT="${PROJ_ROOT:-/tmp/cxx-deps}"
 fi
 
 
 wget https://raw.githubusercontent.com/lz4/lz4/dev/LICENSE -O python/eckitlib/src/copying/liblz4.txt
-echo '{"liblz4": {"path": "copying/liblz4.txt", "home": "https://github.com/lz4/lz4"}}' > python/eckitlib/src/copying/list.json
+
+# Bundle PROJ's data files (proj.db, proj.ini, grids) inside the wheel if we
+# built eckit with PROJ support. The runtime code in eckit/geo/__init__.py
+# points eckit's bundled libproj at this dir via the PROJ context API, so it
+# works offline without any system PROJ install and without leaking PROJ_DATA
+# into the wider process (which would interfere with pyproj/fiona/GDAL/etc.).
+if echo " $CMAKE_PARAMS " | grep -qE '[[:space:]]-DENABLE_PROJ=(1|ON)[[:space:]]' ; then
+    if [ ! -d "$PROJ_ROOT/share/proj" ] ; then
+        echo "ERROR: ENABLE_PROJ=1 but no PROJ data found at $PROJ_ROOT/share/proj" >&2
+        echo "       (override with PROJ_ROOT=/path/to/proj/prefix)" >&2
+        exit 1
+    fi
+    mkdir -p /tmp/eckit/target/eckit/share/proj
+    cp -r "$PROJ_ROOT/share/proj/." /tmp/eckit/target/eckit/share/proj/
+    wget https://raw.githubusercontent.com/OSGeo/PROJ/master/COPYING -O python/eckitlib/src/copying/libproj.txt
+    cat > python/eckitlib/src/copying/list.json <<'JSON'
+{
+  "liblz4": {"path": "copying/liblz4.txt", "home": "https://github.com/lz4/lz4"},
+  "libproj": {"path": "copying/libproj.txt", "home": "https://proj.org"}
+}
+JSON
+else
+    echo '{"liblz4": {"path": "copying/liblz4.txt", "home": "https://github.com/lz4/lz4"}}' > python/eckitlib/src/copying/list.json
+fi
 
 uv pip install cython
diff --git a/share/eckit/geo/ORCA.yaml b/share/eckit/geo/ORCA.yaml
index 4eef547d4..0c2699629 100644
--- a/share/eckit/geo/ORCA.yaml
+++ b/share/eckit/geo/ORCA.yaml
@@ -6,7 +6,7 @@ grid_names:
     name: ORCA2
     intgrid: O42
     arrangement: F
-    shape: [182, 149]
+    shape: [149, 182]
     uid: "174487fbace54b00d959d971e88b71e7"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA2_F.atlas
 
@@ -15,7 +15,7 @@ grid_names:
     name: ORCA2
     intgrid: O42
     arrangement: T
-    shape: [182, 149]
+    shape: [149, 182]
     uid: "d5bde4f52ff3a9bea5629cd9ac514410"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA2_T.atlas
 
@@ -24,7 +24,7 @@ grid_names:
     name: ORCA2
     intgrid: O42
     arrangement: U
-    shape: [182, 149]
+    shape: [149, 182]
     uid: "857f7affa3a381e3882d38d321384e49"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA2_U.atlas
 
@@ -33,7 +33,7 @@ grid_names:
     name: ORCA2
     intgrid: O42
     arrangement: V
-    shape: [182, 149]
+    shape: [149, 182]
     uid: "ca637bc5dc9a54e2ea4b9750e1b79e6e"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA2_V.atlas
 
@@ -42,7 +42,7 @@ grid_names:
     name: ORCA2
     intgrid: O42
     arrangement: W
-    shape: [182, 149]
+    shape: [149, 182]
     uid: "edea6f71eb558dc056b5f576d5b904f7"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA2_T.atlas
 
@@ -51,7 +51,7 @@ grid_names:
     name: ORCA1
     intgrid: O96
     arrangement: F
-    shape: [362, 292]
+    shape: [292, 362]
     uid: "a832a12030c73928133553ec3a8d2a7e"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA1_F.atlas
 
@@ -60,7 +60,7 @@ grid_names:
     name: ORCA1
     intgrid: O96
     arrangement: T
-    shape: [362, 292]
+    shape: [292, 362]
     uid: "f4c91b6233fe55dec992160ec12b38df"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA1_T.atlas
 
@@ -69,7 +69,7 @@ grid_names:
     name: ORCA1
     intgrid: O96
     arrangement: U
-    shape: [362, 292]
+    shape: [292, 362]
     uid: "1b0f8d234753f910197c975c906b4da5"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA1_U.atlas
 
@@ -78,7 +78,7 @@ grid_names:
     name: ORCA1
     intgrid: O96
     arrangement: V
-    shape: [362, 292]
+    shape: [292, 362]
     uid: "c637340454795b395f982851b840943d"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA1_V.atlas
 
@@ -87,7 +87,7 @@ grid_names:
     name: ORCA1
     intgrid: O96
     arrangement: W
-    shape: [362, 292]
+    shape: [292, 362]
     uid: "d50061c43e83c46c3810002591ea21e1"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA1_T.atlas
 
@@ -96,7 +96,7 @@ grid_names:
     name: eORCA1
     intgrid: O96
     arrangement: F
-    shape: [362, 332]
+    shape: [332, 362]
     uid: "3c6d95561710c6f39b394809ff6c588c"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA1_F.atlas
 
@@ -105,7 +105,7 @@ grid_names:
     name: eORCA1
     intgrid: O96
     arrangement: T
-    shape: [362, 332]
+    shape: [332, 362]
     uid: "ba65665a9e68d1a8fa0352ecfcf8e496"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA1_T.atlas
 
@@ -114,7 +114,7 @@ grid_names:
     name: eORCA1
     intgrid: O96
     arrangement: U
-    shape: [362, 332]
+    shape: [332, 362]
     uid: "4eb1054957dcae914e219faf9a4068e3"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA1_U.atlas
 
@@ -123,7 +123,7 @@ grid_names:
     name: eORCA1
     intgrid: O96
     arrangement: V
-    shape: [362, 332]
+    shape: [332, 362]
     uid: "09131429766e7737c087d3a8d7073dc9"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA1_V.atlas
 
@@ -132,7 +132,7 @@ grid_names:
     name: eORCA1
     intgrid: O96
     arrangement: W
-    shape: [362, 332]
+    shape: [332, 362]
     uid: "5c678d8f9aa2edfbf57246d11d9c1278"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA1_T.atlas
 
@@ -141,7 +141,7 @@ grid_names:
     name: ORCA025
     intgrid: O400
     arrangement: F
-    shape: [1442, 1021]
+    shape: [1021, 1442]
     uid: "efbc280d8d4b6048797880da2605bacb"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA025_F.atlas
 
@@ -150,7 +150,7 @@ grid_names:
     name: ORCA025
     intgrid: O400
     arrangement: T
-    shape: [1442, 1021]
+    shape: [1021, 1442]
     uid: "15c961c269ac182ca226d7195f3921ba"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA025_T.atlas
 
@@ -159,7 +159,7 @@ grid_names:
     name: ORCA025
     intgrid: O400
     arrangement: U
-    shape: [1442, 1021]
+    shape: [1021, 1442]
     uid: "3f4a68bc5b54c9f867fbcc12aacc723d"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA025_U.atlas
 
@@ -168,7 +168,7 @@ grid_names:
     name: ORCA025
     intgrid: O400
     arrangement: V
-    shape: [1442, 1021]
+    shape: [1021, 1442]
     uid: "9c87699ee2026c0feee07d2a972eaccd"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA025_V.atlas
 
@@ -177,7 +177,7 @@ grid_names:
     name: ORCA025
     intgrid: O400
     arrangement: W
-    shape: [1442, 1021]
+    shape: [1021, 1442]
     uid: "74ca68f1c8524811f3d3aad99536adc2"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA025_T.atlas
 
@@ -186,7 +186,7 @@ grid_names:
     name: eORCA025
     intgrid: O400
     arrangement: F
-    shape: [1442, 1207]
+    shape: [1207, 1442]
     uid: "770e5bbb667a253d55db8a98a3b2d3a9"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA025_F.atlas
 
@@ -195,7 +195,7 @@ grid_names:
     name: eORCA025
     intgrid: O400
     arrangement: T
-    shape: [1442, 1207]
+    shape: [1207, 1442]
     uid: "983412216c9768bc794c18dc92082895"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA025_T.atlas
 
@@ -204,7 +204,7 @@ grid_names:
     name: eORCA025
     intgrid: O400
     arrangement: U
-    shape: [1442, 1207]
+    shape: [1207, 1442]
     uid: "b1b2922e9b57ee9c6eeddad218b6e4f3"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA025_U.atlas
 
@@ -213,7 +213,7 @@ grid_names:
     name: eORCA025
     intgrid: O400
     arrangement: V
-    shape: [1442, 1207]
+    shape: [1207, 1442]
     uid: "9b06bf73a8f14e927bd9b0f1f0c04f74"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA025_V.atlas
 
@@ -222,7 +222,7 @@ grid_names:
     name: eORCA025
     intgrid: O400
     arrangement: W
-    shape: [1442, 1207]
+    shape: [1207, 1442]
     uid: "4a1ba3b11b8888aefc96992b6b1cab62"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA025_T.atlas
 
@@ -231,7 +231,7 @@ grid_names:
     name: ORCA12
     intgrid: O1600
     arrangement: F
-    shape: [4322, 3059]
+    shape: [3059, 4322]
     uid: "29693ad8a7af3ae3ee0f02d090f0ec7b"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA12_F.atlas
 
@@ -240,7 +240,7 @@ grid_names:
     name: ORCA12
     intgrid: O1600
     arrangement: T
-    shape: [4322, 3059]
+    shape: [3059, 4322]
     uid: "b117d01170ac77bca68560ab10e559de"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA12_T.atlas
 
@@ -249,7 +249,7 @@ grid_names:
     name: ORCA12
     intgrid: O1600
     arrangement: U
-    shape: [4322, 3059]
+    shape: [3059, 4322]
     uid: "fff193b92d94d03e847ff2fa62b493f4"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA12_U.atlas
 
@@ -258,7 +258,7 @@ grid_names:
     name: ORCA12
     intgrid: O1600
     arrangement: V
-    shape: [4322, 3059]
+    shape: [3059, 4322]
     uid: "986e3450774b716f6e75c1987e370b10"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA12_V.atlas
 
@@ -267,7 +267,7 @@ grid_names:
     name: ORCA12
     intgrid: O1600
     arrangement: W
-    shape: [4322, 3059]
+    shape: [3059, 4322]
     uid: "ccfe953619a8dd49a7f765923882a274"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/ORCA12_T.atlas
 
@@ -276,7 +276,7 @@ grid_names:
     name: eORCA12
     intgrid: O1600
     arrangement: F
-    shape: [4322, 3606]
+    shape: [3606, 4322]
     uid: "25da53ed581b3931fa310840fa9aefd9"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA12_F.atlas
 
@@ -285,7 +285,7 @@ grid_names:
     name: eORCA12
     intgrid: O1600
     arrangement: T
-    shape: [4322, 3606]
+    shape: [3606, 4322]
     uid: "1553b66f5885cf5f83ad4b4fdf25f460"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA12_T.atlas
 
@@ -294,7 +294,7 @@ grid_names:
     name: eORCA12
     intgrid: O1600
     arrangement: U
-    shape: [4322, 3606]
+    shape: [3606, 4322]
     uid: "3e87c826643da440b4e9d9f67588a576"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA12_U.atlas
 
@@ -303,7 +303,7 @@ grid_names:
     name: eORCA12
     intgrid: O1600
     arrangement: V
-    shape: [4322, 3606]
+    shape: [3606, 4322]
     uid: "cc1e3fc06a2cd18c0653e557510b8a71"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA12_V.atlas
 
@@ -312,7 +312,7 @@ grid_names:
     name: eORCA12
     intgrid: O1600
     arrangement: W
-    shape: [4322, 3606]
+    shape: [3606, 4322]
     uid: "462469edbd0e0586a0cf17424cc58c89"
     url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA12_T.atlas
 
@@ -358,7 +358,7 @@ grid_uids:
       name: eORCA1
       intgrid: O96
       arrangement: T
-      shape: [362, 332]
+      shape: [332, 362]
       uid: "16076978a048410747dd7c9876677b28"  # (uid older version)
       url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA1_T.atlas
 
@@ -367,7 +367,7 @@ grid_uids:
       name: eORCA1
       intgrid: O96
       arrangement: U
-      shape: [362, 332]
+      shape: [332, 362]
       uid: "7378487847e050559b82d0792374a705"  # (uid older version)
       url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA1_U.atlas
 
@@ -376,6 +376,6 @@ grid_uids:
       name: eORCA1
       intgrid: O96
       arrangement: V
-      shape: [362, 332]
+      shape: [332, 362]
       uid: "d9622b55f3120eafb3dbaf5c742bc56c"  # (uid older version)
       url: https://sites.ecmwf.int/repository/atlas/grids/orca/v0/eORCA1_V.atlas
diff --git a/src/eckit/geo/CMakeLists.txt b/src/eckit/geo/CMakeLists.txt
index 1982aa424..a0bc06060 100644
--- a/src/eckit/geo/CMakeLists.txt
+++ b/src/eckit/geo/CMakeLists.txt
@@ -174,6 +174,7 @@ set(eckit_geo_include_dirs
 )
 
 set(eckit_geo_libs eckit_codec eckit_maths eckit_spec)
+set(eckit_geo_private_libs)
 set(eckit_GEO_SHARE_AREA "~eckit/share/eckit/geo/area.yaml")
 set(eckit_GEO_SHARE_GRID
     "~eckit/share/eckit/geo/grid.yaml"
@@ -193,7 +194,7 @@ if(eckit_HAVE_PROJ)
         projection/PROJ.cc
         projection/PROJ.h
     )
-    list(APPEND eckit_geo_libs PROJ::proj)
+    list(APPEND eckit_geo_private_libs PROJ::proj)
 endif()
 
 if(eckit_HAVE_GEO_AREA_SHAPEFILE)
@@ -203,7 +204,7 @@ if(eckit_HAVE_GEO_AREA_SHAPEFILE)
         cache/Unzip.cc
         cache/Unzip.h
     )
-    list(APPEND eckit_geo_libs shapelib::shp libzip::zip)
+    list(APPEND eckit_geo_private_libs shapelib::shp libzip::zip)
 endif()
 
 string(REPLACE ";" ":" eckit_GEO_SHARE_GRID "${eckit_GEO_SHARE_GRID}")
@@ -224,6 +225,7 @@ ecbuild_add_library(
     INSTALL_HEADERS    ALL
     HEADER_DESTINATION ${INSTALL_INCLUDE_DIR}/eckit/geo
     PUBLIC_LIBS        ${eckit_geo_libs}
+    PRIVATE_LIBS       ${eckit_geo_private_libs}
     PUBLIC_INCLUDES    ${eckit_geo_include_dirs}
     SOURCES            ${eckit_geo_srcs}
 )
diff --git a/src/eckit/geo/Figure.cc b/src/eckit/geo/Figure.cc
index 35659476e..ac7271c7b 100644
--- a/src/eckit/geo/Figure.cc
+++ b/src/eckit/geo/Figure.cc
@@ -15,6 +15,7 @@
 #include <memory>
 
 #include "eckit/geo/Exceptions.h"
+#include "eckit/geo/eckit_geo_config.h"
 #include "eckit/geo/figure/Earth.h"
 #include "eckit/geo/figure/OblateSpheroid.h"
 #include "eckit/geo/figure/Sphere.h"
@@ -23,6 +24,10 @@
 #include "eckit/spec/Custom.h"
 #include "eckit/types/FloatCompare.h"
 
+#if eckit_HAVE_PROJ
+#include "eckit/geo/projection/PROJ.h"
+#endif
+
 
 namespace eckit::geo {
 
@@ -75,6 +80,16 @@ std::string Figure::spec_str() const {
 }
 
 
+std::string Figure::proj_str() const {
+#if eckit_HAVE_PROJ
+    std::unique_ptr<const spec::Custom> custom(spec());
+    return projection::PROJ::proj_str(*custom);
+#else
+    NOTIMP;
+#endif
+}
+
+
 bool Figure::spherical() const {
     return types::is_approximately_equal(a(), b());
 }
diff --git a/src/eckit/geo/LibEcKitGeo.cc b/src/eckit/geo/LibEcKitGeo.cc
index 6a4752817..911cf366f 100644
--- a/src/eckit/geo/LibEcKitGeo.cc
+++ b/src/eckit/geo/LibEcKitGeo.cc
@@ -21,6 +21,10 @@
 #include "eckit/geo/eckit_geo_config.h"
 #include "eckit/utils/StringTools.h"
 
+#if eckit_HAVE_PROJ
+#include "eckit/geo/projection/PROJ.h"
+#endif
+
 
 namespace eckit {
 
@@ -172,6 +176,18 @@ bool LibEcKitGeo::proj() {
 }
 
 
+bool LibEcKitGeo::ensureProjDatabase(const std::string& fallback_db,
+                                     const std::vector<std::string>& fallback_search_paths) {
+#if eckit_HAVE_PROJ
+    return geo::projection::PROJ::proj_database_available(fallback_db, fallback_search_paths);
+#else
+    static_cast<void>(fallback_db);
+    static_cast<void>(fallback_search_paths);
+    return false;
+#endif
+}
+
+
 const void* LibEcKitGeo::addr() const {
     return this;
 }
diff --git a/src/eckit/geo/LibEcKitGeo.h b/src/eckit/geo/LibEcKitGeo.h
index 1d5cc7fdc..798e7ecdd 100644
--- a/src/eckit/geo/LibEcKitGeo.h
+++ b/src/eckit/geo/LibEcKitGeo.h
@@ -12,6 +12,7 @@
 
 #pragma once
 
+#include <string>
 #include <vector>
 
 #include "eckit/system/Library.h"
@@ -50,6 +51,13 @@ class LibEcKitGeo final : public system::Library {
 
     static bool proj();
 
+    /**
+     *  If PROJ has a usable database.
+     *  @return true if PROJ has a usable database, false otherwise
+     */
+    static bool ensureProjDatabase(const std::string& fallback_db,
+                                   const std::vector<std::string>& fallback_search_paths = {});
+
     std::string version() const override;
     std::string gitsha1(unsigned int count) const override;
 
diff --git a/src/eckit/geo/area/library/Shapefile.cc b/src/eckit/geo/area/library/Shapefile.cc
index d06f1b203..119e856ff 100644
--- a/src/eckit/geo/area/library/Shapefile.cc
+++ b/src/eckit/geo/area/library/Shapefile.cc
@@ -17,6 +17,8 @@
 #include <ostream>
 #include <vector>
 
+#include "shapefil.h"
+
 #include "eckit/geo/Exceptions.h"
 #include "eckit/geo/LibEcKitGeo.h"
 #include "eckit/geo/area/Polygon.h"
@@ -31,6 +33,15 @@
 namespace eckit::geo::area::library {
 
 
+// PIMPL body: holds the shapelib-typed state so <shapefil.h> stays out of the
+// installed public header. Kept in the .cc so that the unique_ptr in the
+// Shapefile class only sees a complete Implementation type where its
+// destructor is instantiated (i.e. in ~Shapefile() below).
+struct Shapefile::Implementation {
+    SHPInfo* shp = nullptr;
+};
+
+
 namespace {
 
 
@@ -91,16 +102,19 @@ Shapefile::Shapefile(const PathName& file) : Shapefile(file, "") {}
 
 
 Shapefile::Shapefile(const PathName& shp, const PathName& dbf, const std::string& name) :
-    shpPath_(path_shp(shp)), dbfPath_(path_dbf(dbf, shpPath_)), nEntities_(0) {
+    shpPath_(path_shp(shp)),
+    dbfPath_(path_dbf(dbf, shpPath_)),
+    impl_(std::make_unique<Implementation>()),
+    nEntities_(0) {
     Log::debug<LibEcKitGeo>() << "eckit::geo::area::library::Shapefile(shp='" << shpPath_.realName() << "',dbf='"
                               << dbfPath_.realName() << "',name='" << name << "')" << std::endl;
 
-    if ((shp_ = SHPOpen(shpPath_.localPath(), "rb")) == nullptr) {
+    if ((impl_->shp = SHPOpen(shpPath_.localPath(), "rb")) == nullptr) {
         throw CantOpenFile(shpPath_ + " (as .shp)", Here());
     }
 
     int type = 0;
-    SHPGetInfo(shp_, &nEntities_, &type, nullptr, nullptr);
+    SHPGetInfo(impl_->shp, &nEntities_, &type, nullptr, nullptr);
 
     if (type != SHPT_ARC && type != SHPT_POLYGON) {
         throw ReadError("Shapefile: unsupported shape type", Here());
@@ -142,7 +156,7 @@ Shapefile::Shapefile(const PathName& shp, const PathName& dbf, const std::string
 
 
 Shapefile::~Shapefile() {
-    SHPClose(shp_);
+    SHPClose(impl_->shp);
 }
 
 
@@ -200,7 +214,7 @@ Area* Shapefile::make_area(size_t entity) const {
         explicit Object(SHPObject* ptr) : unique_ptr{ptr, SHPDestroyObject} { ASSERT(operator bool()); }
     };
 
-    Object obj(SHPReadObject(shp_, static_cast<int>(entity)));
+    Object obj(SHPReadObject(impl_->shp, static_cast<int>(entity)));
     ASSERT(obj);
     ASSERT(obj->nSHPType == SHPT_ARC || obj->nSHPType == SHPT_POLYGON);
 
diff --git a/src/eckit/geo/area/library/Shapefile.h b/src/eckit/geo/area/library/Shapefile.h
index 3922e0301..fd5bada78 100644
--- a/src/eckit/geo/area/library/Shapefile.h
+++ b/src/eckit/geo/area/library/Shapefile.h
@@ -14,13 +14,12 @@
 
 #include <iosfwd>
 #include <map>
+#include <memory>
 #include <string>
 
 #include "eckit/filesystem/PathName.h"
 #include "eckit/geo/area/Library.h"
 
-#include "shapefil.h"
-
 
 namespace eckit::geo {
 class Area;
@@ -65,12 +64,16 @@ class Shapefile : public Library {
 
 private:
 
+    // -- Types
+
+    struct Implementation;
+
     // -- Members
 
     const PathName shpPath_;
     const PathName dbfPath_;
 
-    SHPInfo* shp_;
+    std::unique_ptr<Implementation> impl_;
 
     std::string name_;
     int nEntities_;
diff --git a/src/eckit/geo/figure/OblateSpheroid.cc b/src/eckit/geo/figure/OblateSpheroid.cc
index 0958ab478..be8741738 100644
--- a/src/eckit/geo/figure/OblateSpheroid.cc
+++ b/src/eckit/geo/figure/OblateSpheroid.cc
@@ -86,7 +86,7 @@ double OblateSpheroid::_area(double a, double b, const area::BoundingBox& bbox)
     const auto dlam = util::DEGREE_TO_RADIAN * (bbox.east() - bbox.west());
 
     const auto e = eccentricity(a, b);
-    const auto A = dlam * a * b * (f(phi2, e) - f(phi1, e));
+    const auto A = dlam * b * b / 2. * (f(phi2, e) - f(phi1, e));
 
     return A;
 }
diff --git a/src/eckit/geo/projection/PROJ.cc b/src/eckit/geo/projection/PROJ.cc
index 5d6ebc5eb..38297c5f8 100644
--- a/src/eckit/geo/projection/PROJ.cc
+++ b/src/eckit/geo/projection/PROJ.cc
@@ -14,10 +14,13 @@
 
 #include <proj.h>
 
+#include <cstdlib>
 #include <map>
 #include <set>
 #include <utility>
+#include <vector>
 
+#include "eckit/filesystem/PathName.h"
 #include "eckit/geo/Exceptions.h"
 #include "eckit/geo/Figure.h"
 #include "eckit/spec/Custom.h"
@@ -32,11 +35,23 @@ static ProjectionRegisterType<PROJ> PROJECTION("proj");
 namespace {
 
 
-constexpr auto CTX = PJ_DEFAULT_CTX;
+constexpr auto CTX              = PJ_DEFAULT_CTX;
+constexpr PJ_AREA* DEFAULT_AREA = nullptr;
 
 
 struct pj_t : std::unique_ptr<PJ, decltype(&proj_destroy)> {
-    explicit pj_t(element_type* ptr) : unique_ptr(ptr, &proj_destroy) {}
+    explicit pj_t(element_type* ptr) : unique_ptr(ptr, &proj_destroy) {
+        if (!operator bool()) {
+            // common errors are "proj.db not found" or "invalid CRS string"
+            const auto err = proj_context_errno(CTX);
+            throw exception::ProjectionError(
+                "PROJ: failed to create object (err=" + std::to_string(err) + ", description='" +
+                    proj_errno_string(err) +
+                    "'). Ensure proj.db is available (https://proj.org/en/stable/resource_files.html) or install "
+                    "the eckitlib wheel which bundles its own).",
+                Here());
+        }
+    }
 };
 
 
@@ -93,7 +108,7 @@ struct XYZ final : Convert {
 
 
 Figure* make_figure(const std::string& proj_str) {
-    pj_t identity(proj_create_crs_to_crs(CTX, proj_str.c_str(), proj_str.c_str(), nullptr));
+    pj_t identity(proj_create_crs_to_crs(CTX, proj_str.c_str(), proj_str.c_str(), DEFAULT_AREA));
 
     pj_t crs(proj_get_target_crs(CTX, identity.get()));
     pj_t ellipsoid(proj_get_ellipsoid(CTX, crs.get()));
@@ -142,7 +157,7 @@ PROJ::PROJ(const std::string& source, const std::string& target, double lon_mini
     ASSERT(!target_.empty());
 
     auto make_convert = [lon_minimum](const std::string& string) -> Convert* {
-        pj_t identity(proj_create_crs_to_crs(CTX, string.c_str(), string.c_str(), nullptr));
+        pj_t identity(proj_create_crs_to_crs(CTX, string.c_str(), string.c_str(), DEFAULT_AREA));
         pj_t crs(proj_get_target_crs(CTX, identity.get()));
         pj_t cs(proj_crs_get_coordinate_system(CTX, crs.get()));
         ASSERT(cs);
@@ -158,11 +173,10 @@ PROJ::PROJ(const std::string& source, const std::string& target, double lon_mini
     };
 
     // projection, normalised
-    auto ctx = PJ_DEFAULT_CTX;
+    pj_t p(proj_create_crs_to_crs(CTX, source_.c_str(), target_.c_str(), DEFAULT_AREA));
+    p.reset(proj_normalize_for_visualization(CTX, p.release()));
 
-    implementation_ = std::make_unique<Implementation>(
-        proj_normalize_for_visualization(ctx, proj_create_crs_to_crs(ctx, source_.c_str(), target_.c_str(), nullptr)),
-        ctx, make_convert(source_), make_convert(target_));
+    implementation_ = std::make_unique<Implementation>(p.release(), CTX, make_convert(source_), make_convert(target_));
     ASSERT(implementation_);
 }
 
@@ -260,6 +274,67 @@ const std::string& PROJ::proj_default() {
 }
 
 
+bool PROJ::proj_database_available(const std::string& fallback_db,
+                                   const std::vector<std::string>& fallback_search_paths) {
+    // Resolution order:
+    //   1. If PROJ can resolve a database on its own (via its compiled-in default search paths, e.g. a system install)
+    //   2. If @p fallback_db points at a @c proj.db file, with @p fallback_search_paths used to locate @c proj.ini and
+    //   grid files.
+    //
+    // The fallback is applied via the PROJ per-context API, so it affects only eckit's libproj instance and never leaks
+    // into other PROJ users in the process (pyproj, fiona, GDAL, ...). It is a no-op when eckit was built without PROJ
+    // support. Intended to be called once, at initialisation, before any PROJ-backed projection is created.
+
+    struct Database {
+        Database(const std::string& fallback_db, const std::vector<std::string>& fallback_search_paths) {
+            auto database_available = [&]() -> bool {
+                const auto previous_level = proj_log_level(CTX, PJ_LOG_NONE);
+
+                auto avail = false;
+                try {
+                    pj_t crs(proj_create_from_database(CTX, "EPSG", "4326", PJ_CATEGORY_CRS, false, nullptr));
+                    avail = static_cast<bool>(crs);
+                }
+                catch (...) {
+                }
+
+                proj_log_level(CTX, previous_level);
+                return avail;
+            };
+
+            // (1) If PROJ already finds a usable database on its own, leave it alone.
+            if (database_available()) {
+                available = true;
+                return;
+            }
+
+            // (2) Only now fall back to the provided (bundled) database, if present.
+            if (!fallback_db.empty() && PathName{fallback_db}.exists()) {
+                proj_context_set_database_path(CTX, fallback_db.c_str(), nullptr, nullptr);
+
+                std::vector<const char*> paths;
+                paths.reserve(fallback_search_paths.size());
+                for (const auto& p : fallback_search_paths) {
+                    if (!p.empty() && PathName{p}.exists()) {
+                        paths.push_back(p.c_str());
+                    }
+                }
+
+                if (!fallback_search_paths.empty()) {
+                    proj_context_set_search_paths(CTX, static_cast<int>(paths.size()), paths.data());
+                }
+
+                available = database_available();
+            }
+        }
+
+        bool available = false;
+    } static const DATABASE(fallback_db, fallback_search_paths);
+
+    return DATABASE.available;
+}
+
+
 void PROJ::fill_spec(spec::Custom& custom) const {
     custom.set("type", "proj");
     if (source_ != proj_default()) {
diff --git a/src/eckit/geo/projection/PROJ.h b/src/eckit/geo/projection/PROJ.h
index 8ec1a7190..eff500f63 100644
--- a/src/eckit/geo/projection/PROJ.h
+++ b/src/eckit/geo/projection/PROJ.h
@@ -51,6 +51,13 @@ class PROJ : public Projection {
     static std::string proj_str(const spec::Custom&);
     static const std::string& proj_default();
 
+    /**
+     *  If PROJ has a usable database.
+     *  @return true if PROJ has a usable database, false otherwise
+     */
+    static bool proj_database_available(const std::string& fallback_db,
+                                        const std::vector<std::string>& fallback_search_paths = {});
+
 private:
 
     // -- Types