diff --git a/common/map.h b/common/map.h
index dfee5b43b7..dfbec09ba6 100644
--- a/common/map.h
+++ b/common/map.h
@@ -572,7 +572,7 @@ extern const int DIR_DY[8];
 #else  /* FREECIV_WEB */
 #define MAP_DEFAULT_SIZE         4
 #define MAP_MIN_SIZE             0
-#define MAP_MAX_SIZE             2048
+#define MAP_MAX_SIZE             18
 #endif /* FREECIV_WEB */
 
 FC_STATIC_ASSERT(MAP_MAX_SIZE * 1000 <= MAX_DBV_LENGTH,