Eight hundred metres long, these ramparts and nine towers, dating from c. 14C, formerly encircled the entire city. Access to the sentry path is through the Schirmerturm, rebuilt after a fire in spring 1994. It is also possible to go up into the Zytturm, home to the city's oldest clock (1535) and the Männliturm. Enjoy the fine view of the town with the steeple of the collegiate of St-Léger, and the lake in its mountain setting.