diff --git a/src/roadveh.h b/src/roadveh.h
--- a/src/roadveh.h
+++ b/src/roadveh.h
@@ -22,4 +22,23 @@ static inline bool IsRoadVehInDepotStopp
 void CcBuildRoadVeh(bool success, TileIndex tile, uint32 p1, uint32 p2);
 void CcCloneRoadVeh(bool success, TileIndex tile, uint32 p1, uint32 p2);
 
+
+/**
+ * This class 'wraps' Vehicle; you do not actually instantiate this class.
+ * You create a Vehicle using AllocateVehicle, so it is added to the pool
+ * and you reinitialize that to a Train using:
+ *   v = new (v) RoadVehicle();
+ *
+ * As side-effect the vehicle type is set correctly.
+ */
+struct RoadVehicle : public Vehicle {
+	/** Initializes the Vehicle to a road vehicle */
+	RoadVehicle() { this->type = VEH_ROAD; }
+
+	/** We want to 'destruct' the right class. */
+	virtual ~RoadVehicle() {}
+
+	const char *GetTypeString() { return "road vehicle"; }
+};
+
 #endif /* ROADVEH_H */