The Château Deganne is one of the most prominent buildings on Arcachon's Boulevard du Général de Gaulle, a grand 19th-century villa in the eclectic style characteristic of the Ville d'Été. Built in the 1860s for a wealthy Bordelais family, the building later served as the town's casino and is now a cultural centre hosting exhibitions and events.
The exterior, with its towers and ornate stonework, represents the architectural ambitions of the early Arcachon resort — built with Bordeaux wine money at a time when the railway had just made the town accessible to the wealthy middle classes. The building's gardens front onto the main promenade; it's best admired from outside if no exhibition is running, though the interior is worth visiting when events are scheduled.