diff --git a/boards/cache.py b/boards/cache.py
index c5c2962..c692bd7 100644
--- a/boards/cache.py
+++ b/boards/cache.py
@@ -2,4 +2,5 @@ from boards.models import Board
 
 
 def board_last_modified_at(request, board_slug):
-    return Board.objects.filter(slug=board_slug).first().refreshed_at
+    board = Board.objects.filter(slug=board_slug).first()
+    return board.refreshed_at if board else None