Before 2017, the municipality was in the Schanfigg sub-district of the Plessur district, after that date it was part of the Plessur Region. Located on the south-east slope of the Weisshorn chain, the town of Arosa is at the top of the Schanfigg valley at the foot of the Aroser Weisshorn (). Adjoining are the areas of Innerarosa, Dorf-Obersee, Untersee and Maran-Prätschli at an elevation of .