In Austria, if you celebrate a round birthday, or something else of particular note (eg. A wedding), don’t be surprised if people turn up at your house at 4am with fireworks. And no… I’m not kidding. Not quite sure where this crazy tradition comes from, but it’s a common, and accepted occurrence. A whole group of your nearest and dearest will get together, bring along some fireworks, some food and some music, and shoot rockets off in the dead of the night to wake you up on your big day.