Château d'Annecy, Medieval castle and museum in Annecy, France.

Château d'Annecy is a castle perched on a hilltop featuring thick stone walls, multiple towers, and construction elements from different centuries blended together. The structure combines various architectural styles developed over hundreds of years of occupation and modification.

Built during the 12th century as a residence for the Counts of Geneva, this castle later served the Dukes of Genevois-Nemours as their seat. It was subsequently transformed into military barracks, marking a shift from noble dwelling to military use.

The castle displays regional art collections featuring Alpine furniture, religious sculptures, and landscape paintings created by local artists. These works reflect how people in the region lived and saw their surroundings.

The castle stands on the last rocky spur of the Semnoz above the town, at 470 m altitude, overlooking the Thiou and its island. The museum occupies the Logis Vieux and Logis Nemours, while the Tower and Logis Perrière hold the Alpine Lakes Regional Observatory. The terrace looks over the old town's narrow streets and roofs.

The Tour de la Reine, the castle's oldest section, has walls over 4 m thick. Since 1993 the tower and the adjoining Logis Perrière have housed the Observatoire régional des lacs alpins, whose displays cover lakeside archaeology, fish of the mountain lakes, a model of Lake Annecy and the evolution of boats on the lake.