Sion, called Sitten in German, is the capital of the Canton of Valais. The Old Town, which lies between the hills of Valère and Tourbillon, dates back to the Middle Ages and is home to numerous sights and attractions, such as one of the world's oldest organs that can still be played.
Sion's history dates back to the Stone Age, as demonstrated by 5,000 year old stone menhirs and one of Switzerland's largest celtic necropolises. The hill of Valère with its basilica was named after the mother of a Roman city prefect. The foundations of the collegiate church, which was mentioned in historical documents for the first time 1000 years ago, were already laid in Celtic times. The church is home to an organ from the 15th century.
The ruins of the erstwhile bishop's castle from the 13th century lie on the adjacent hill of Tourbillon. Further attractions in the medieval Old Town include the Cathedral of Notre-Dame-du-Glarier (which dates back to the 15th century) and the Witches' Tower, which was part of the old city fortifications.