It includes paved roads in the Alps that are over 1 kilometre (0.62 miles) long and whose culminating point is over 1,850 metres (6,070 feet) above sea level.
This height approximately corresponds to that of the highest major settlements in the country.
[1] Some of the listed roads are closed to motorised vehicles, although they are normally all accessible to pedestrians and cyclists.
These mountain roads are popular with drivers, bikers and cyclists for their spectacular scenery and are often the highlights of bicycle races such as Tour de Suisse and Tour de Romandie.
As the tree line lies at approximately 2,000 metres in the Alps, almost all the upper sections of the listed roads are in the alpine zone, where the main form of precipitation becomes snow.