Fronted by a row of sequoia-sized Corinthian columns, Australia's largest city hall was built between 1920 and 1930. Although free, fascinating heritage tours (45 minutes) of the sandstone behemoth should be booked in advance (online or by phone); they can be available on the day from the excellent on-site Museum of Brisbane, however, so always consider checking. Alternatively, free tours of the building's 85m-high clock tower run every 15 minutes from 10am to 5pm; grab tickets from the museum.
Interestingly, the marble in City Hall's foyer was sourced from the same Tuscan quarry as that used by Michelangelo to sculpt his David. It's one of many fascinating details about the building. The Rolling Stones played their first-ever Australian gig in its magnificent auditorium in 1965, itself complete with a 4300-pipe organ, mahogany and blue-gum floors, and offering free concerts at noon every Tuesday from February to November.