diff --git a/scripts/geodata/polygons/language_polys.py b/scripts/geodata/polygons/language_polys.py
index 683843ac..a26d3c6f 100644
--- a/scripts/geodata/polygons/language_polys.py
+++ b/scripts/geodata/polygons/language_polys.py
@@ -22,6 +22,7 @@ class LanguagePolygonIndex(RTreePolygonIndex):
         'qs_a1r_lc',
         'qs_level',
         'languages',
+        'admin_level'
     ])
 
     @classmethod