The city of Thun, which is located at the lower end of Lake Thun, is the gate to the Bernese Oberland. The historic Old Town is situated about one kilometer from the shore of the lake, on the river Aare. There is a castle in the center of the Old Town that dates back to the 12th century and boasts a museum.
The first settlement arose on today's site of the city as early as 2,500 BC. The mighty castle was constructed by the Dukes of Zähringen. It has a fortification tower built between 1180 and 1190. The halls of the tower house a historical museum that exhibits artifacts from prehistory and early history as well as medieval objects, weapons and uniforms from the 18th and 19th century. The castle's most splendid exhibit is the restored Knights Hall, dating to the 12th century.
Further sights in the Old Town include the town church with its tower dating back to about 1330, the town hall from the 16th century, the Old Town itself and the numerous restaurants and cafés along the Aare River.