flows northwest to the Lenne. The Hundem is fed from the south by the Heinsberger Bach – also known as the Albaumer Bach (Bach is German for "brook") –...

nature reserve of Haberg (625.4 m; Heinsberger Hochheide) it runs over the 637.9 m high crest of the closed Heinsberg Tunnel (1,303 m long) and then heads...