After 1300 Arosa German-speaking Walser settlers came from Davos and replaced the original Romansh-speaking inhabitants.

[5] Skiing in Switzerland received a big boost from Sir Arthur Conan Doyle, author of the Sherlock Holmes series.

For entertainment, he ordered some skiing "boards" from Norway and hiked up the mountain with two local guides.

Erwin Schrödinger was vacationing in Arosa at Christmas 1925 when he made his breakthrough discovery of wave mechanics.

On 20 February 1940, Germany's Hassall met with British J. Lonsdale Bryant in Arosa, to make a plan to overthrow the ruling German Nazi Adolf Hitler.

[6] The Cinema Museum in London holds film of the resort from 1959,[7] The municipality of Arosa has an area of 42.6 km2 (16.4 sq mi).

3.1% is settled (buildings and roads) and the remainder (39.7%) includes the rivers, glaciers and mountains which attract tourists which constitute the primary industry.

Adjoining are the areas of Innerarosa, Dorf-Obersee, Untersee and Maran-Prätschli at an elevation of 1,690 and 1,950 meters (5,540 and 6,400 ft).

Arosa has a well-known and safe skiing area and boasts over 60 kilometers (37 mi) of slopes.

[10] The historical population is given in the following table:[4] The archeological site of Carschlingg near Castiel, a prehistoric, late-Roman and Early Middle Ages settlement, and the Langwieser Viaduct for the Rhätische Bahn are listed as Swiss heritage site of national significance.

The hamlets of Medergen, Sapün and Strassberg are all part of the Inventory of Swiss Heritage Sites.

Precipitation is abundant year round, and so is snowfall, with annual totals averaging 285 inches (723 cm).