Schadau Palace is situated in the Schaudaupark, and was built between 1846 and 1854 according to the plans of Pierre-Charles Dusillon in the Gothic Revival style, for the banker Abraham Denis Alfred de Rougemont
Since 1925 the castle has belonged to the city of Thun and contains a restaurant and the Swiss Gastronomy Museum. Between 1972 and 1992 the façade of the castle was renovated by the city's own quarrymen.
The oldest known surviving panorama was completed in 1814 by Marquard Wocher, and is on display at the Schadau Castle, depicting an average morning in the Swiss town of Thun. As of today it's owned by the Gottfried Keller Foundation.References:
First record of Kastelholma (or Kastelholm) castle is from the year 1388 in the contract of Queen Margaret I of Denmark, where a large portion of the inheritance of Bo Jonsson Grip was given to the queen. The heyday of the castle was in the 15th and 16th centuries when it was administrated by Danish and Swedish kings and stewards of the realms. Kastelhoma was expanded and enhanced several times.
In the end of 16th century castle was owned by the previous queen Catherine Jagellon (Stenbock), an enemy of the King of Sweden Eric XIV. King Eric conquered Kastelholma in 1599 and all defending officers were taken to Turku and executed. The castle was damaged under the siege and it took 30 years to renovate it.
In 1634 Åland was joined with the County of Åbo and Björneborg and Kastelholma lost its administrative status.