621
xkcd #2922: Pub Trivia
(imgs.xkcd.com)
Alt text:
Bonus question: Where is London located? (a) The British Isles (b) Great Britain and Northern Ireland (c) The UK (d) Europe (or 'the EU') (e) Greater London
Only Melbourne was previously the official capital of the federated colonies which became the Commonwealth of Australia. Sydney was, and still is, the capital of NSW - but was never the capital of the country.