Southeastern round tower, Kronoberg castle ruin
Kronoberg Castle in Kronoberg County, Sweden is a medieval ruin. Kronoberg Castle is located on the shore of Lake Helgasjön. In the 15th century, the Bishop of Växjö built fortifications that could serve as a place of safety in case of attack (most likely by the Danes). Kronoberg was taken over by rebels in 1542 when the Dacke revolt occurred, led by Nils Dacke. This revolt was suppressed in 1543 when the King took over the Bishop's Kronoberg castle and the surrounding land. The king was now seeing a stronghold of support to prevent new rebellions. He continued strengthening the castle, and when it was fully built in 1580, it had at least 50 cannons. After the Treaty of Roskilde was signed in 1658, Kronoberg castle was no longer important militarily. It began to decay and soon became a ruin.