Arosa is a town and a municipality in the district of Plessur in the canton of Graubünden in Switzerland. It is both a summer and a winter tourist resort.
On 1 January 2013, the former municipalities of Calfreisen, Castiel, Langwies, Lüen, Molinis, Peist and St. Peter-Pagig merged into the municipality of Arosa.
At the end of 2013 the Arosa ski resort was linked with Lenzerheide by cable-car, creating the new ski resort of Arosa Lenzerheide. Since then transport passes work in both resorts.
The town is known throughout Switzerland for its famous ice hockey team, the EHC Arosa which is one of the most successful teams in the country.