The construction of defensive tower, the oldest part of Hulterstad Church, was completed around the year 1200. There are also some remains of older building from the early 1100’s below the ground. In 1803 the church was reconstructed to the present, single-nave and rectangular shape.
The interior originates from several centuries. Oldest artefacts are the baptismal font and the painted consecration cross from Middle Ages. Mural paintings in arches were painted in the 1600s. The large bell was made in 1631 by Jurgen Putensen. The organs date from 1867, designed by L. Hedin. In 1676 the royal warship wrecked outside Hulterstad and a most of the crew were buried in the cemetery.
There is a small museum in one of the tower's floors including some runestones. Some stones have been found under the tower's ground floor.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.