The Majorie is a high tower dominating the site and protected by imposing terraced walls.

On 15 January 1373, the castle was bought by Bishop Guichard Tavelli, and served from then on as the official residence for the Prince-bishops of Sion.

The Majorie tower probably contained reception rooms, and the buildings that served as bishops' habitation have not been preserved.

Despite several reconstruction projects, the castle was left as it was, and the bishops eventually built their palace near the Sion Cathedral in 1839–1840.

The Grange-à-l'Évêque (Bishop's Barn), the former stables of the castle, has been home to the Valais Nature Museum [fr] since 2013.