Secret Key Sites in Zurich (Ehgraben & Lindenhofkeller)

At the Stadthaus Zürich, special keys can be picked up at counter S during opening hours, allowing visitors to explore historic places that are otherwise locked. The Ehgraben is a hidden passageway through which the city of Zurich's wastewater was once channelled, accessible through a very narrow door. A narrow staircase also leads to the late medieval city wall and an early water conduit. On the Lindenhof is the Lindenhofkeller, another exclusively accessible underground site.