diff --git a/mapmaker/flatmap/__init__.py b/mapmaker/flatmap/__init__.py
index e5decea0..39db7f74 100644
--- a/mapmaker/flatmap/__init__.py
+++ b/mapmaker/flatmap/__init__.py
@@ -263,6 +263,11 @@ def duplicate_feature_id(self, feature_ids: str) -> bool:
     #========================================================
         return self.__features_with_id.get(feature_ids, None) is not None
 
+    def remove_feature_id(self, feature_id: str):
+    #=============================================
+        # Free up an id so another feature can be registered with it
+        self.__features_with_id.pop(feature_id, None)
+
     def feature_to_geojson_ids(self, feature_ids: list[str]) -> list[int]:
     #=====================================================================
         return [f.geojson_id for id in feature_ids
diff --git a/mapmaker/properties/pathways.py b/mapmaker/properties/pathways.py
index ad624f7c..6384cc8b 100644
--- a/mapmaker/properties/pathways.py
+++ b/mapmaker/properties/pathways.py
@@ -944,7 +944,9 @@ def __route_network_connectivity(self, network: Network):
                     # Add a polygon feature for a nerve cuff
                     properties = feature.properties.copy()
                     feature.properties.pop('models', None)  # Otherwise we can get two markers on the feature
-                    properties.pop('id', None)   # Otherwise we will have a duplicate id...
+                    if (feature_id := feature.properties.pop('id', None)) is not None:
+                        # The polygon, not the dashed outline, should own the feature id
+                        self.__flatmap.remove_feature_id(feature_id)
                     nerve_polygon_feature = self.__flatmap.new_feature(
                         'pathways',
                         shapely.geometry.Polygon(feature.geometry.coords).buffer(0), properties)