diff --git a/libraries/AC_Fence/examples/AC_Fence_test/AC_Fence_test.pde b/libraries/AC_Fence/examples/AC_Fence_test/AC_Fence_test.pde
index 231286bff9..01cc3621c3 100644
--- a/libraries/AC_Fence/examples/AC_Fence_test/AC_Fence_test.pde
+++ b/libraries/AC_Fence/examples/AC_Fence_test/AC_Fence_test.pde
@@ -28,6 +28,7 @@
 #include <AC_Fence.h>           // Fence library
 #include <GCS_MAVLink.h>
 #include <AP_Mission.h>
+#include <AP_Terrain.h>
 #include <AP_Notify.h>
 #include <AP_Vehicle.h>
 #include <DataFlash.h>