diff --git a/airport.c b/airport.c
--- a/airport.c
+++ b/airport.c
@@ -1,5 +1,6 @@
 #include "stdafx.h"
 #include "ttd.h"
+#include "map.h"
 #include "airport.h"
 
 AirportFTAClass *CountryAirport;