The Hornberg–Triberg–St. Georgen segment of the Schwarzwaldbahn is one of Germany's most scenic train rides. The 149-km (93-miles) Schwarzwaldbahn, built from 1866 to 1873, runs from Offenburg to Lake Constance via Triberg. It has no fewer than 39 tunnels, and at one point climbs almost 2,000 feet in just 11 km (6½ miles). It's now part of the German Railway, and you can make inquiries at any station.