diff --git a/landscape.c b/landscape.c
index f10e699ca7..67806fad89 100644
--- a/landscape.c
+++ b/landscape.c
@@ -444,7 +444,11 @@ void SetMapExtraBits(uint tile, byte bits)
 
 uint GetMapExtraBits(uint tile)
 {
-	return (_map_extra_bits[tile >> 2] >> (tile&3)*2)&3;
+	if (GET_TILE_X(tile) < MapSizeX() && GET_TILE_Y(tile) < MapSizeY() &&
+			GET_TILE_X(tile) > 0 && GET_TILE_Y(tile) > 0)
+		return (_map_extra_bits[tile >> 2] >> (tile&3)*2)&3;
+	else
+		return 0;
 }
 
 #define TILELOOP_BITS 4