diff --git a/src/c3nav/mapdata/schemas/models.py b/src/c3nav/mapdata/schemas/models.py
index 6ad98a42..a3277c2a 100644
--- a/src/c3nav/mapdata/schemas/models.py
+++ b/src/c3nav/mapdata/schemas/models.py
@@ -385,6 +385,7 @@ class CustomLocationSchema(SerializableSchema):
         description="ground altitude (in the map-wide coordinate system), if it can be determined"
     )
     geometry: Optional[PointSchema] = APIField(
+        None,
         description="point geometry for this custom location",
     )