diff --git a/direct/src/level/EntityTypes.py b/direct/src/level/EntityTypes.py
index 8e2fe0b15b..9265465cd9 100755
--- a/direct/src/level/EntityTypes.py
+++ b/direct/src/level/EntityTypes.py
@@ -56,6 +56,7 @@ class Zone(Entity, NodepathAttribs):
     attribs = (
         ('description', ''),
         ('modelZoneNum', None),
+        ('visibility', []),
         )
 
 class BarrelBase(Nodepath):