The ruins of the Wolfsburg by the western approach to Neustadt an der Weinstraße lie on a rocky crag on the Wolfsberg hill. It was built in the early 13th century by Count Palatine Louis I. During the Peasants' War in 1525 it was conquered and looted two times and finally destroyed during the Thirty Years' War in 1633. Until that it has been ruined.
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.