It is located a few kilometres south of Freiburg im Breisgau, in the south-western part of Baden-Württemberg.

Au lies in the northern part of Hexental between Schönberg in the west and Black Forest to the east.

[4] Neighbouring communities include Horben in the southeast, Wittnau, Baden-Württemberg in the southwest, Ebringen in the west and Merzhausen in the north, as well as Freiburg im Breisgau to the east.

[citation needed] The Upper Rhine Plain fault line runs through Au.

The turnout was at 68.9%, up from 2009 (68.4%) *Wählergemeinschaft für Bürgernähe und Umweltschutz Because almost half of the local land is agriculturally useful, the economic sector still plays a significant role.