Mo church ruin probably date back to around 1215, and this may well be Norway`s smallest free-standing stone church from medieval times.
It is believed that it was originally a privately owned church. However, Mo parish is mentioned in both 1368 and 1400. The oldest coins found are form King Sverre`s reign 1177-1202, and the most recent ones are from reign of King Hans who died in 1513. These indicate the period during which the church was in use.
The church was probably in use until the Reformation, but in 1743 all that remained were tall ruins which slowly became covered in earth and vegetation.
During the period 1972-1977, the ruins were dug out and restored. Service is held in the ruins once every summer. The full outline of the church is now clearly visible. Behind the altar, the wall has been rebuilt with a gothic window and main altarpiece.
Among the finds were three pieces of medieval gravestones from around 1200, decorative fittings and part of a brass bell from the Middle Age. North of the church, skeletons of five young women were discovered. They were approx. 25 years of age and around 1,5 meters tall, and this could be a mass-grave from the Black Death period in 1350.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.