Chillon Castle is an island castle located on Lake Geneva (Lac Léman), south of Veytaux in the canton of Vaud, Switzerland. It is situated at the eastern end of the lake, on the narrow shore between Montreux and Villeneuve, which gives access to the Alpine valley of the Rhône. Chillon is amongst the most visited medieval castles in Switzerland and Europe. Successively occupied by the house of Savoy then by the Bernese from 1536 until 1798, it now belongs to the State of Vaud and is classified as a Swiss Cultural Property of National Significance.

The first written mention of Chillon Castle dates back to 1150. At that time, the castle was owned by the Counts of Savoy. It was in a very strategic location, nestled between the mountains and the lake, on a connecting route from the north to the south – the Via Francigena. The Savoy family controlled the route that passed in front of the castle and led to the new town of Villeneuve, a path trodden by travellers, merchants and pilgrims heading towards Rome via the Great Saint Bernard Alpine Pass. The Counts of Savoy profited from this thoroughfare by installing a toll to cover security and maintenance costs for the road.

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