diff --git a/lib/main.js b/lib/main.js
index 38f85e3..5fd96d6 100644
--- a/lib/main.js
+++ b/lib/main.js
@@ -87,7 +87,13 @@ function (moment, Router, L, GUI, numeral) {
           ids = [d.source.node.nodeinfo.node_id, d.target.node.nodeinfo.node_id]
         d.id = ids.join("-")
 
-        if (unknown || !("location" in d.source.node.nodeinfo && "location" in d.target.node.nodeinfo))
+        if (unknown ||
+            !d.source.node.nodeinfo.location ||
+            !d.target.node.nodeinfo.location ||
+            isNaN(d.source.node.nodeinfo.location.latitude) ||
+            isNaN(d.source.node.nodeinfo.location.longitude) ||
+            isNaN(d.target.node.nodeinfo.location.latitude) ||
+            isNaN(d.target.node.nodeinfo.location.longitude))
           return
 
         d.latlngs = []