Rising to 473m, Schlossberg is the site of the original fortress where Graz was founded and is marked by the city's most visible icon – the Uhrturm. Its wooded slopes can be reached by a number of bucolic and strenuous paths, but also by lift or Schlossbergbahn funicular. It's a brief walk or take tram 4 or 5 to Schlossplatz/Murinsel for the lift. A fun way of getting back down is on the Schlossberg Slide.
To avoid a walk back late at night, bear in mind that the lift operates from 8am to 12.30am daily, and the funicular from 9am to midnight from Sunday to Wednesday and until 2am from Thursday to Saturday.