diff --git a/src/c3nav/mapdata/utils/geometry.py b/src/c3nav/mapdata/utils/geometry.py
index 1582d091..6f037b4f 100644
--- a/src/c3nav/mapdata/utils/geometry.py
+++ b/src/c3nav/mapdata/utils/geometry.py
@@ -1,3 +1,4 @@
+import json
 import math
 from collections import deque, namedtuple
 from itertools import chain