Kastelholm's walls

The lower part of the walls of 14 AD was built with local granite and had a height of 6-9 meters. It's height in the 15AD was increased up to 16.5 m and the wall was fitted with a wooden parapet on the top. At the beginning of the 16AD height of the wall has been further increased by 2 m. and musket and cannon loopholes were made.