The formerly free Altenau is part of the resort Altenau-Schulenberg in the Upper Harz in the mountain and university town of Clausthal-Zellerfeld in the district of Goslar in Lower Saxony. Altenau is a nationally recognized health resort in the Upper Harz. Altenau received 1617 municipal rights in the year. From 1972 to 2014, the Altenau belonged to the oberharz.