diff --git a/tests/domain/spline-corridor-colliders.test.ts b/tests/domain/spline-corridor-colliders.test.ts
new file mode 100644
index 00000000..5f94ec35
--- /dev/null
+++ b/tests/domain/spline-corridor-colliders.test.ts
@@ -0,0 +1,106 @@
+import { describe, expect, it } from "vitest";
+
+import { createScenePath } from "../../src/document/paths";
+import { createTerrain } from "../../src/document/terrains";
+import { deriveSplineCorridorBoxColliders } from "../../src/spline-corridor/spline-corridor-colliders";
+
+describe("spline corridor colliders", () => {
+  it("derives simple box colliders for collision-enabled repeaters", () => {
+    const path = createScenePath({
+      id: "path-repeater-collision",
+      repeaters: [
+        {
+          id: "repeater-fence-collision",
+          assetId: "fence_segment_wood_2m",
+          collisionEnabled: true,
+          placement: "center",
+          spacing: 2,
+          terrainConform: false,
+          randomScale: 0,
+          randomYawDegrees: 0
+        }
+      ],
+      points: [
+        {
+          id: "point-a",
+          position: { x: 0, y: 0, z: 0 }
+        },
+        {
+          id: "point-b",
+          position: { x: 4, y: 0, z: 0 }
+        }
+      ]
+    });
+
+    const colliders = deriveSplineCorridorBoxColliders({ paths: [path] });
+
+    expect(colliders).toHaveLength(3);
+    expect(colliders[0]).toMatchObject({
+      kind: "box",
+      source: "splineCorridor",
+      pathId: path.id,
+      repeaterId: "repeater-fence-collision",
+      assetId: "fence_segment_wood_2m",
+      position: { x: 0, y: 0, z: 0 },
+      rotationDegrees: { x: 0, y: 90, z: 0 },
+      center: { x: 0, y: 0.565, z: 0 },
+      size: { x: 0.14, y: 1.13, z: 2.04 }
+    });
+  });
+
+  it("derives terrain-conformed curb edge box colliders", () => {
+    const terrain = createTerrain({
+      id: "terrain-corridor-collision",
+      position: { x: 0, y: 1, z: 0 },
+      sampleCountX: 2,
+      sampleCountZ: 2,
+      cellSize: 4,
+      heights: [1, 1, 1, 1]
+    });
+    const path = createScenePath({
+      id: "path-curb-collision",
+      road: {
+        enabled: true,
+        width: 2,
+        heightOffset: 0.05,
+        terrainConform: true,
+        edges: {
+          left: {
+            enabled: true,
+            collisionEnabled: true,
+            kind: "curb",
+            width: 0.4,
+            height: 0.2,
+            materialId: null
+          }
+        }
+      },
+      points: [
+        {
+          id: "point-a",
+          position: { x: 0, y: 10, z: 0 }
+        },
+        {
+          id: "point-b",
+          position: { x: 4, y: 10, z: 0 }
+        }
+      ]
+    });
+
+    const colliders = deriveSplineCorridorBoxColliders({
+      paths: [path],
+      terrains: [terrain]
+    });
+
+    expect(colliders).toEqual([
+      expect.objectContaining({
+        pathId: path.id,
+        edgeSide: "left",
+        position: { x: 2, y: 2.15, z: 1.2 },
+        rotationDegrees: { x: 0, y: 90, z: 0 },
+        center: { x: 0, y: 0, z: 0 },
+        size: { x: 0.4, y: 0.2, z: 4 }
+      })
+    ]);
+  });
+});