Schloßberg, Hill with park in central Graz, Austria

The Schloßberg is a tree-covered dolomite hill rising 123 m above Graz's main square, topped by a park with the Uhrturm clock tower and Glockenturm bell tower. Its slopes hold two surviving castle bastions, the 94 m Türkenbrunnen cistern, and the Kasemattenbühne open-air stage in a former bastion cellar. The clock tower's white walls, dark shingled roof and round clock faces stand above a red-brick terrace with arched openings.

A Romanesque castle was built on the bare rock around 1125, giving Graz its name from the Slavic "gradec", small castle. From 1544 Domenico dell'Allio and later Simone Genga turned it into a Renaissance fortress, recorded in the Guinness Book as the strongest fortress of all time. It was never taken by force: after Napoleon occupied Vienna in 1809, the coerced city surrendered and the works were razed, except the clock and bell towers, which citizens bought free. Ludwig von Welden began turning the hill into a park in 1839.

The Kasemattenbühne, an open-air stage set in the cellar of a ruined bastion, seats 1,310 people and has a retractable roof for bad weather. Each year the Elevate Festival brings contemporary music, art and political debate to venues on and around the hill. The name Schloßberg keeps the old spelling with ß, as the city treats it as a proper name.

The funicular runs from Kaiser-Franz-Josef-Kai on the west side up to the casemates and the hilltop restaurant. A pair of lifts rises from Schloßbergplatz through a 77-metre shaft to a café just above the clock tower. Steep paths climb from all four sides, and cyclists are formally forbidden.

The tunnel system beneath the hill was built as a shelter during the Second World War and continues to serve as a path for exploration and events today. These underground passages add an unexpected layer to visiting the site.