This elegant late-14th-century tower was built not only as a fortification but also as a triumphal arch marking the entrance to the Old Town. Like the bridge itself, it was designed by Peter Parler and incorporates many symbolic elements. Inside is an exhibition about the design and construction of bridge and tower, including artefacts retrieved by archaelologists from the bed of the river. However, the main justification for paying the admission fee is the amazing view from the top of the tower.