Mainau is an island in Lake Constance (on the south shore of the Überlinger See near the city of Konstanz, Baden-Württemberg, Germany). It is maintained as a garden island and a model of excellent environmental practices. Administratively, the island has been a part of Konstanz since December 1, 1971, when the municipality of Litzelstetten, of which Mainau was part, was incorporated into Konstanz. Mainau is still part of Litzelstetten, now one of 15 wards (administrative subdivisions) of Konstanz.