Roman Catholic Diocese of Sion Roman Catholic Diocese of Sion The Diocese of Sion (, , ) is a Roman Catholic ecclesiastical territory in the canton of Valais, Switzerland. It is the oldest bishopric in the country and one of the oldest north of the Alps. The history of the Bishops of Sion, of the Abbey of St. Maurice of Valais as a whole are inextricably intertwined. The see was established at Octodurum, now called Martigny, the capital of the Roman province of Alpes Poeninae. The first authentically historical bishop was Saint Theodore/Theodolus (died in 391), who was present at the Council of Aquileia in
Sion District the question. Sion town has an average of 82.6 days of rain or snow per year and on average receives of precipitation. The wettest month is December during which time Sion receives an average of of rain or snow. During this month there is precipitation for an average of 7.4 days. The month with the most days of precipitation is August, with an average of 8.2, but with only of rain or snow. The driest month of the year is April with an average of of precipitation over 5.9 days. In Sion about 11,917 or (32.2%) of the population have