diff --git a/tests/regression_tests/lattice_rotated/__init__.py b/tests/regression_tests/lattice_rotated/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/tests/regression_tests/lattice_rotated/inputs_true.dat b/tests/regression_tests/lattice_rotated/inputs_true.dat
new file mode 100644
index 0000000000..8ee34b4f39
--- /dev/null
+++ b/tests/regression_tests/lattice_rotated/inputs_true.dat
@@ -0,0 +1,71 @@
+
+
+ |
+ |
+ |
+ |
+ |
+ |
+ |
+ |
+
+ 1.25
+ 30
+ 0.0 0.0
+
+ 2
+ 1 1
+1 2 1
+ 1 1
+1 2 1
+ 1 1
+1 1 1
+ 1 1
+ 1
+
+
+ 1.25 1.25
+ 30
+ 4 4
+ -2.5 -2.5
+
+2 2 2 2
+1 1 1 1
+1 1 1 1
+1 1 1 1
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+ eigenvalue
+ 1000
+ 5
+ 0
+
+
+ 0.0 0.0 0.0
+
+
+
diff --git a/tests/regression_tests/lattice_rotated/results_true.dat b/tests/regression_tests/lattice_rotated/results_true.dat
new file mode 100644
index 0000000000..b92298cc29
--- /dev/null
+++ b/tests/regression_tests/lattice_rotated/results_true.dat
@@ -0,0 +1,2 @@
+k-combined:
+4.538090E-01 2.452457E-02
diff --git a/tests/regression_tests/lattice_rotated/test.py b/tests/regression_tests/lattice_rotated/test.py
new file mode 100644
index 0000000000..9cab92e1e6
--- /dev/null
+++ b/tests/regression_tests/lattice_rotated/test.py
@@ -0,0 +1,85 @@
+import numpy as np
+import openmc
+
+from tests.testing_harness import PyAPITestHarness
+
+
+def rotated_lattice_model():
+ model = openmc.model.Model()
+
+ # Create some materials
+ fuel1 = openmc.Material()
+ fuel1.set_density('g/cm3', 10.0)
+ fuel1.add_nuclide('U235', 1.0)
+ fuel2 = openmc.Material()
+ fuel2.set_density('g/cm3', 10.0)
+ fuel2.add_nuclide('U238', 1.0)
+ water = openmc.Material()
+ water.set_density('g/cm3', 1.0)
+ water.add_nuclide('H1', 2.0)
+ water.add_nuclide('O16', 1.0)
+ water.add_s_alpha_beta('c_H_in_H2O')
+ model.materials.extend([fuel1, fuel2, water])
+
+ # Create universes for lattices
+ r_pin = openmc.ZCylinder(r=0.25)
+ fuel_cell = openmc.Cell(fill=fuel1, region=-r_pin)
+ water_cell = openmc.Cell(fill=water, region=+r_pin)
+ pin_universe = openmc.Universe(cells=(fuel_cell, water_cell))
+ r_big_pin = openmc.ZCylinder(r=0.5)
+ fuel2_cell = openmc.Cell(fill=fuel2, region=-r_big_pin)
+ water2_cell = openmc.Cell(fill=water, region=+r_big_pin)
+ big_pin_universe = openmc.Universe(cells=(fuel2_cell, water2_cell))
+ all_water_cell = openmc.Cell(fill=water)
+ outer_universe = openmc.Universe(30, cells=(all_water_cell,))
+
+ # Create hexagonal lattice
+ pitch = 1.25
+ hexlat = openmc.HexLattice()
+ hexlat.center = (0., 0.)
+ hexlat.pitch = [pitch]
+ hexlat.outer = outer_universe
+ outer_ring = [big_pin_universe] + [pin_universe]*11
+ middle_ring = [big_pin_universe] + [pin_universe]*5
+ inner_ring = [big_pin_universe]
+ hexlat.universes = [outer_ring, middle_ring, inner_ring]
+
+ # Create rectangular lattice
+ rectlat = openmc.RectLattice()
+ rectlat.center = (0., 0.)
+ rectlat.pitch = (pitch, pitch)
+ rectlat.lower_left = (-2*pitch, -2*pitch)
+ rectlat.outer = outer_universe
+ rectlat.universes = np.full((4, 4), pin_universe)
+ rectlat.universes[0] = big_pin_universe
+
+ # Create cell filled with translated/rotated rectangular lattice on left
+ left_cyl = openmc.ZCylinder(x0=-4.0, r=4.0)
+ left_cell = openmc.Cell(fill=rectlat, region=-left_cyl)
+ left_cell.translation = (-4.0, 0.0, 0.0)
+ left_cell.rotation = (0.0, 0.0, 45.0)
+
+ # Create cell filled with translated/rotated hexagonal lattice on right
+ right_cyl = openmc.ZCylinder(x0=4.0, r=4.0)
+ right_cell = openmc.Cell(fill=hexlat, region=-right_cyl)
+ right_cell.translation = (4.0, 0.0, 0.0)
+ right_cell.rotation = (0.0, 0.0, 30.0)
+
+ # Finish up with the geometry
+ outer_cyl = openmc.ZCylinder(r=8.0, boundary_type='vacuum')
+ main_cell = openmc.Cell(fill=water, region=-outer_cyl & +left_cyl & +right_cyl)
+ model.geometry = openmc.Geometry([main_cell, left_cell, right_cell])
+
+ model.settings.batches = 5
+ model.settings.inactive = 0
+ model.settings.particles = 1000
+ model.settings.source = openmc.Source(space=openmc.stats.Point())
+ model.settings.export_to_xml()
+
+ return model
+
+
+def test():
+ model = rotated_lattice_model()
+ harness = PyAPITestHarness('statepoint.5.h5', model)
+ harness.main()