Altendorf is a village in Saxony, Germany, situated in the district of Sächsische Schweiz-Osterzgebirge. It lies on the S154 road that links Bad Schandau and Sebnitz. It was one of the villages that composed the municipality of Kirnitzschtal, but, since 1 October 2012, it has been part of the municipality of Sebnitz.
Coordinates: 50°56′08″N 14°10′55″E / 50.935527°N 14.181891°E