The Basilica church of St. Ursula was is built upon the ancient ruins of a Roman cemetery. The church has an impressive reliquary created from the bones of the former occupants of the cemetery. It is one of the twelve Romanesque churches of Cologne and was designated a Minor Basilica in 1920. While the nave and crossing tower are Romanesque, the choir has been rebuilt in the Gothic style.
The Golden Chamber, or Goldene Kammer, of the church contains the alleged remains of St. Ursula and her 11,000 virgins who are said to have been killed by the Huns, possibly around the time of the Battle of the Catalaunian Plains. The original legend said only 11 virgins accompanied St. Ursula but the number grew over time, eventually to 11,000. The walls of the Golden Chamber are covered in bones arranged in designs and/or letters along with relic skulls. The exact number of people whose remains are in the Golden Chamber remains ambiguous but the number of skulls in the reliquary is greater than 11 and less than 11,000. These remains were found in 1106 in a mass grave and were assumed to be those of the legend of St. Ursula and the 11,000 virgins. Therefore, the church constructed the Golden Chamber to house the bones. The bones themselves are neatly arranged in 'zigzags and swirls and even in the shapes of Latin words.'
References:When are Saturday and Sunday Masses held?
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.