Trips last between 2-6 hours depending on the location.
There are approximately 100 ancient hillforts in Finland. They were in use from the Viking Age to the Crusade period, i.e. from 9th to the 13th century. They are on steap ridges or outcrops of bedrock, difficult to reach by foot. In many places hillforts were visible from each other and served as a beacon system inwards the country.