The Sydney Opera House is situated next to the city's harbour.
It isn't just for operas it is used for concerts and plays too.
The Opera House was designed by the Danish architect Jorn Utzon.
The construction work was started in 1958, and the Opera House was completed 15 years later.
It was opened by Queen Elizabeth II in 1973.
The roof is(was) made of concrete, and it is(was) covered with more than a million white tiles.