DB AutoZug GmbH was a German rail transport company that provided automobile (Motorail) and night passenger train services for Deutsche Bahn AG. It was based in Dortmund and was a wholly owned subsidiary of Deutsche Bahn AG. On 30 September 2013 the company was merged into DB AG's long-distance division DB Fernverkehr.

The Hindenburgdamm or Hindenburg Dam is an 11 km-long causeway joining the North Frisian island of Sylt to mainland Schleswig-Holstein. Its coordinates are 54°53′N 8°33′E. It was opened on 1 June 1927 and is exclusively a railway corridor. The companies that built the Hindenburgdamm, a job that took four years, were Philipp Holzmann AG of Frankfurt, working from the mainland, and Peter Fix Söhne of Duisburg working from Sylt. A train trip along the causeway takes about 10 minutes, and the time between the auto terminals at Niebüll on the mainland and Westerland on Sylt is about 30 minutes. The Hindenburgdamm is part of the railway line known as the Marschbahn, which is double-tracked along much of the route, although there as yet exists a single-tracked stretch. On the causeway is a signal box. The rail line is not electrified making the use of diesel locomotives necessary. Trains coming from origins further south like Hamburg change from an electric locomotive to a diesel locomotive at Itzehoe.