diff --git a/src/rail_gui.cpp b/src/rail_gui.cpp
index bab6b4c555..267caee17e 100644
--- a/src/rail_gui.cpp
+++ b/src/rail_gui.cpp
@@ -2011,6 +2011,7 @@ 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);
 	}