diff --git a/src/c3nav/routing/router.py b/src/c3nav/routing/router.py
index 03a5cd0f..44ca2abc 100644
--- a/src/c3nav/routing/router.py
+++ b/src/c3nav/routing/router.py
@@ -421,8 +421,8 @@ class Router:
         graph[space_nodes, :] = np.inf
         graph[:, space_nodes] = np.inf
         if restrictions.additional_nodes:
-            graph[restrictions.additional_nodes, :] = np.inf
-            graph[:, restrictions.additional_nodes] = np.inf
+            graph[tuple(restrictions.additional_nodes), :] = np.inf
+            graph[:, tuple(restrictions.additional_nodes)] = np.inf
         graph[restrictions.edges.transpose().tolist()] = np.inf
 
         distances, predecessors = shortest_path(graph, directed=True, return_predecessors=True)