The canton of Valais (French pronunciation: [valɛ]; German: Wallis, German pronunciation: [ˈvalɪs]) is one of the 26 cantons of Switzerland, situated in the southwestern part of the country, around the valley of the Rhône from its headwaters to Lake Geneva, separating the Pennine Alps from the Bernese Alps. The canton is simultaneously one of the driest regions of Switzerland in its central Rhône valley and among the wettest, having large amounts of snow and rain up on the highest peaks found in Switzerland. The canton of Valais is widely known for the Matterhorn and resort towns such as Crans-Montana, Saas Fee and Zermatt. It is composed of 13 districts (hence the 13 stars on the flag) and its capital is Sion.

The Romans called the upper Rhône valley Vallis Poenina. The Vallis Poenina was won by the Romans after a great fight at Octodurus (Martigny) in 57 B.C., and was so thoroughly Romanized that both the Celtic original inhabitants and the Germanic Burgundian invaders of the 5th century, became Romance-speaking people. According to a tradition which can be traced back to the middle of the 8th century, the Theban legion was martyred at Agaunum (now Saint Maurice) about 285 or 302. From 888 onwards the lands were part of the kingdom of Jurane Burgundy.

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