Sion

capital of Valais canton, southwestern Switzerland. It lies along the Rhone River, at the mouth of La Sionne River, southeast of Lake Geneva (Lac Leman). It originated as a Celtic and Roman settlement called Sedunum. Sion became the seat of a bishop in the late 6th century, and from 999 the bishops of Sion held the spiritual and temporal power in Valais, which they retained, at least in part, until 1798. The two hillocks that dominate the town are crowned by the remains of the 13th-century Chateau de Tourbillon and those of the Chateau de Valere (Valeria), now containing a historical museum and a mainly 13th-century church. Other notable buildings are the Cathedral of Notre-Dame-du-Glarier, the Church of Saint-Theodule (1516), the Maison Supersaxo (1505), the town hall (1660), and the remains of the Chateau de la Majorie, now housing an art gallery. The town is on the road and rail routes from Lausanne to Milan via the Simplon Pass. It is an important market for vegetables, fruit, and wine. The population is predominantly French speaking. Pop. (2007 est.) 28,633.

canton, southern Switzerland. It borders Italy to the south and France to the west and is bounded by the cantons of Vaud and Bern on the north and Uri and Ticino on the east. Its area includes the valley of the upper Rhone River, from its source at the Rhone Glacier to its mouth on Lake Geneva; the valley runs from east to west and then, in a right angle at Martigny, from southeast to northwest. From just above Saint-Maurice, the Rhone's right bank belongs to Vaud canton. The mountain chains of the Bernese and the Pennine Alps border the Rhone River valley, and on each side lateral valleys open; those of the south are spread out and inhabited, and those of the north are steep and largely uninhabited, with the exception of the Lotschental (Lotschen Valley) and Leukerbad (Loeche-les-Bains).