The Gracar Turn ('Grätzer's Tower') is not recorded in medieval sources, though the historian Valvasor mentions a manor stood on the site in the 14th century, built by the Grätzer family from nearby Gradac, whence its name derives. After passing through numerous hands, it was purchased by Anton Rudež in 1821. The author Janez Trdina was often Rudež's guest at Gracar Turn; several of the former's works were written at the castle, including his best-known, Fables and Tales of the Gorjancers. During World War II part the castle was burned down by partisan fighters. It has since been renovated.
The core of the castle consists of a multi-story residential palacium, surrounded by a rectangular complex anchored by two imposing square towers.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.