evidence: Roughly speaking, the Black Forest forms an elongated rectangle between Karlsruhe, Stuttgart, Basle and Lake Constance. The Black Forest borders on France in the west and Switzerland in the south. The towns and villages and tourist attractions in the Black Forest can be quickly reached by car via the two autobahns running east and west of the Black Forest, the A5 (Rhine Valley Autobahn, Karlsruhe - Basle) and A81 (Lake Constance Autobahn, Stuttgart - Singen).