Waldemarsudde, originally the home of Prince Eugen, son of Oscar II (1865-1947), became state-owned after the Prince's death and in accordance with his will, and is now among the most-visited art museums in Sweden. The complex consists of a castle-like main building - the Mansion - finished in 1905, and a Gallery Building, added in 1913. The estate also includes the original manor-house building, known as the Old House and an old linseed mill, both dating back to the 1780s.