Sydney is the most populous city in Australia. It has appeared multiple times in Overwatch media.
In Going Legit, Junkrat and Roadhog are hired by the CEO of Hyde Global to rescue the company's workers from omnic terrorists. After finding out the CEO was lying to get them arrested, the two blow up the company's skyscraper.
In Reflections, Junkrat and Roadhog have returned to Sydney to cause mayhem at Luna Park.