diff --git a/src/Prep/UserDef/sample.xml b/src/Prep/UserDef/sample.xml
index a2e01064..35fe332d 100644
--- a/src/Prep/UserDef/sample.xml
+++ b/src/Prep/UserDef/sample.xml
@@ -91,6 +91,7 @@ villages, lakes etc. for your own scenery with tguserdef.
 
  <polygon>
   <name>Kanata (north end)</name>
+  <material>Urban</material>
   <contour>
    <hole>false</hole>
    <v>