What is the biggest news story in your opinion that you either witnessed first hand or heard was big news.
For me worldwide I'd say:
Fall of the Berlin wall
The Moon landing
9/11
Germany surrendering after WW2
For Australia:
Harold Holt going missing. Yes, Australia is the country so casual we misplaced our head of state. Not only that, it's extremely likely that he drowned, so what did we name in his honor? A swimming pool.