Château d'Ouchy

Château d’Ouchy in Lausanne, Switzerland, is a lakeside castle begun around 1170 by the medieval bishops of Lausanne and rooted in the high medieval period, with a later nineteenth-century neo-Gothic rebuilding that gives the site its present look. The complex served as an episcopal residence for centuries, played roles in regional administration and confinement, and was the place where the 1923 Treaty of Lausanne was signed, an international agreement that reshaped the borders and population arrangements between Greece and Turkey after the Greco-Turkish War.

The earliest phase began with a residential tower erected about 1170 by Bishop Landri de Durnes. In about 1207 Count Thomas de Maurienne destroyed that tower, which was rebuilt soon after by Bishop Roger I of Vico Pisano. By the late thirteenth century the place had become the bishop’s house and by 1283 it was described as a castle serving as the episcopal residence.

Around 1283 the original tower was incorporated into a fortified complex surrounded by a ring wall, with service buildings and a palas, the main residential block, that contained a large hall. Major building work during the late thirteenth and early fourteenth centuries is linked to Bishop Guillaume II de Champvent, who also renewed the summer residence at Lucens and gave the lakeside site an appearance modeled on his rebuilt seigneurial dwelling at Champvent.

In the fifteenth century local people from nearby villages were obliged to maintain the fortifications and could shelter within the walls, and Bishop Wilhelm de Varax, who lived at the castle in the mid-1400s, appears to have enlarged the site further and provided a bishop’s prison. After the Bernese conquest of the Vaud region during the Reformation in 1536, the castle passed into Bernese hands and was used as a prison.

A serious fire in 1609 destroyed the central tower and much of the defenses through arson; the complex was rebuilt afterwards but then fell into progressive disuse and its fabric was taken away for building stone. The main tower, however, survived and was used for storage and as a granary until 1761. Late seventeenth- and eighteenth-century activity included the erection of new buildings within the defensive enclosure, permission to operate a large oven on the east side, and the renewal and addition of structures during the eighteenth century.

In 1885 the Canton sold the partly restored property to a private owner who removed the older ruined buildings while keeping the tower, which was modernized. Between 1889 and 1893 the site was rebuilt in a neo-Gothic style and converted into a hotel, producing the ensemble’s present appearance. On 24 July 1923 the Treaty of Lausanne was concluded there, revising earlier settlements and arranging a population exchange between Greece and Turkey while defining contemporary borders. Today the château functions as a hotel and is recognized as cultural property of regional significance in Switzerland.