Thun Castle was Built at the end of the 12th century by the Dukes of Zähringen.
The castle museum is housed in the five floors of the tower and includes cultural and historic displays showing the development of the region over some 4,000 years.
In 2006, the castle was bought by the city of Thun from the canton of Bern. Until the end of 2009, the Bernese Oberland regional court was based in the castle.
The castle was the seat of the local court and since at least the 17th century there was a prison under the roof of the donjon. In 1886 a new prison was built on the castle grounds. Two years later, in 1888, the museum opened in the castle.
Thun Castle is a Swiss heritage site of national significance.