On the Old Town side of Charles Bridge, this Gothic tower built in 1373 is flanked by sculptures of St. Vitus and Charles IV. Open to the public, it offers excellent views of the Old Town and the Vltava River to visitors who climb the narrow staircase. The tower once displayed the heads of twelve Protestant leaders executed in 1621, and was also the site of the final conflict of the Thirty Years War (1618-1648).