diff --git a/.cirrus.yml b/.cirrus.yml
index 8a51e1a7..4470d972 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -32,6 +32,25 @@ env:
   CONDA_CACHE_PACKAGES: "nox pip pyyaml"
   # Use specific custom iris source feature branch.
   IRIS_SOURCE: "github:mesh-data-model"
+  # Git commit hash for iris test data.
+  IRIS_TEST_DATA_VERSION: "2.2"
+  # Base directory for the iris-test-data.
+  IRIS_TEST_DATA_DIR: ${HOME}/iris-test-data
+  OVERRIDE_TEST_DATA_REPOSITORY: ${IRIS_TEST_DATA_DIR}/test_data
+
+
+#
+# YAML alias for the iris-test-data cache.
+#
+iris_test_data_template: &IRIS_TEST_DATA_TEMPLATE
+  data_cache:
+    folder: ${IRIS_TEST_DATA_DIR}
+    fingerprint_script:
+      - echo "iris-test-data v${IRIS_TEST_DATA_VERSION}"
+    populate_script:
+      - wget --quiet https://github.com/SciTools/iris-test-data/archive/v${IRIS_TEST_DATA_VERSION}.zip -O iris-test-data.zip
+      - unzip -q iris-test-data.zip
+      - mv iris-test-data-${IRIS_TEST_DATA_VERSION} ${IRIS_TEST_DATA_DIR}
 
 
 #
@@ -97,6 +116,7 @@ test_task:
       - echo "${CIRRUS_TASK_NAME}"
       - echo "${NOX_CACHE_BUILD}"
       - if [ -n "${IRIS_SOURCE}" ]; then echo "${IRIS_SOURCE}"; fi
+  << : *IRIS_TEST_DATA_TEMPLATE
   test_script:
     - export CONDA_OVERRIDE_LINUX="$(uname -r | cut -d'+' -f1)"
     - nox --session tests -- --verbose
diff --git a/esmf_regrid/tests/integration/experimental/__init__.py b/esmf_regrid/tests/integration/experimental/__init__.py
new file mode 100644
index 00000000..00ac6516
--- /dev/null
+++ b/esmf_regrid/tests/integration/experimental/__init__.py
@@ -0,0 +1 @@
+"""Integration tests for :mod:`esmf_regrid.experimental`."""
diff --git a/esmf_regrid/tests/integration/experimental/unstructured_scheme/__init__.py b/esmf_regrid/tests/integration/experimental/unstructured_scheme/__init__.py
new file mode 100644
index 00000000..8819d721
--- /dev/null
+++ b/esmf_regrid/tests/integration/experimental/unstructured_scheme/__init__.py
@@ -0,0 +1 @@
+"""Integration tests for :mod:`esmf_regrid.experimental.unstructured_scheme`."""
diff --git a/esmf_regrid/tests/integration/experimental/unstructured_scheme/test_regrid_unstructured_to_rectilinear.py b/esmf_regrid/tests/integration/experimental/unstructured_scheme/test_regrid_unstructured_to_rectilinear.py
new file mode 100644
index 00000000..d7aafe31
--- /dev/null
+++ b/esmf_regrid/tests/integration/experimental/unstructured_scheme/test_regrid_unstructured_to_rectilinear.py
@@ -0,0 +1,50 @@
+"""Integration tests for :func:`esmf_regrid.experimental.unstructured_scheme.regrid_unstructured_to_rectilinear`."""
+
+
+import os
+
+import iris
+from iris.experimental.ugrid import PARSE_UGRID_ON_LOAD
+import numpy as np
+
+from esmf_regrid.experimental.unstructured_scheme import (
+    regrid_unstructured_to_rectilinear,
+)
+
+
+def test_real_data():
+    """
+    Test for :func:`esmf_regrid.experimental.unstructured_scheme.regrid_unstructured_to_rectilinear`.
+
+    Tests with cubes derived from realistic data.
+    """
+    # Load source cube.
+    test_data_dir = iris.config.TEST_DATA_DIR
+    src_fn = os.path.join(
+        test_data_dir, "NetCDF", "unstructured_grid", "lfric_surface_mean.nc"
+    )
+    with PARSE_UGRID_ON_LOAD.context():
+        src = iris.load_cube(src_fn, "rainfall_flux")
+
+    # Load target grid cube.
+    tgt_fn = os.path.join(
+        test_data_dir, "NetCDF", "global", "xyt", "SMALL_hires_wind_u_for_ipcc4.nc"
+    )
+    tgt = iris.load_cube(tgt_fn)
+
+    # Perform regridding.
+    result = regrid_unstructured_to_rectilinear(src, tgt)
+
+    # Check data.
+    assert result.shape == (1, 160, 320)
+    assert np.isclose(result.data.mean(), 2.93844e-5)
+    assert np.isclose(result.data.std(), 2.71724e-5)
+
+    # Check metadata.
+    assert result.metadata == src.metadata
+    assert result.coord("time") == src.coord("time")
+    assert result.coord("latitude") == tgt.coord("latitude")
+    assert result.coord("longitude") == tgt.coord("longitude")
+    assert result.coord_dims("time") == (0,)
+    assert result.coord_dims("latitude") == (1,)
+    assert result.coord_dims("longitude") == (2,)