Khertvisi is one of the oldest fortresses in Georgia and was functional throughout the Georgian feudal period. It was first built in the 2nd century BC. The church was built in 985, and the present walls were built in 1354. As the legend says, Khertvisi was destroyed by Alexander the Great.
In the 10th-11th centuries it was the center of Meskheti region. During the 12th century it became a town. In the 13th century Mongols destroyed it and until the 15th century it lost its power. In the 15th century it was owned by Meskheti landlords from Jakeli family. In the 16th century the southern region of Georgia was invaded by Turks. During next 300 years they have owned Khertvisi too.
At the end of the 19th century Georgian and Russian army returned the lost territories and Khertvisi became the military base for Russian and Georgian troops. Khertvisi fortress is situated on the high rocky hill in the narrow canyon at the confluence of the Mtkvari and Paravani Rivers.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.