The Mittenwald railway was built as an electric local railway from 1910 to 1912 by the engineers and contractors Josef Riehl and Wilhelm Carl von Doderer. The route was opened on 28 October 1912 and operated jointly by the Austrian Federal Railways and the Royal Bavarian State Railways. It was one of the first lines operated with high-tension single-phase AC-powered trains. Thus it had a substantial impact on the development of standards for electric railway operations in Central Europe. Together with the Ausserfern Railway (Ausserfernbahn) it connects the Austrian district of Außerfern (located west of the Fern Pass) with the Tyrol through Germany.