diff --git a/src/settings_gui.cpp b/src/settings_gui.cpp
index 576f49db06..e5056457cc 100644
--- a/src/settings_gui.cpp
+++ b/src/settings_gui.cpp
@@ -35,6 +35,7 @@
 
 #include "table/sprites.h"
 #include "table/strings.h"
+#include <map>
 
 static const StringID _units_dropdown[] = {
 	STR_GAME_OPTIONS_MEASURING_UNITS_IMPERIAL,