The Great Church (Grote Kerk) dates from the 15th century. Prior to the Protestant Reformation it was named for St. Vitus. It survived the Spanish invasion of 1572 and the subsequent burning of the town. The church has numerous wooden vaults that are painted with scenes from the Old and New Testaments. These were hidden for many years and were only rediscovered in a recent restoration. The church is the venue for a number of cultural activities such as organ music nights and the bi-annual Naarden Photo festival.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.