diff --git a/src/rail_gui.cpp b/src/rail_gui.cpp
index c54e172a0c..c9b04ee29d 100644
--- a/src/rail_gui.cpp
+++ b/src/rail_gui.cpp
@@ -2015,6 +2015,7 @@ struct BuildRailWaypointWindow : PickerWindowBase {
 		this->FinishInitNested(TRANSPORT_RAIL);
 
 		matrix->SetCount(_waypoint_count);
+		if (_cur_waypoint_type >= _waypoint_count) _cur_waypoint_type = 0;
 		matrix->SetClicked(_cur_waypoint_type);
 	}