Parliament House
The seat of Australian federal government, opened in 1988 — the largest building in the southern hemisphere by floor area, designed to be walked over rather than around (the lawn-covered roof was deliberate, public symbolism). Free guided tours run hourly; visitors can sit in the public galleries during sitting weeks and watch debate, Question Time and committee proceedings. Don't miss the Marble Foyer, the Great Hall tapestry, and the rooftop view at sunset.