The system circulates cold water from the harbour through 35 kilometres of pipes to power both the heating and air conditioning in the building. Sydney Opera House is cooled using seawater taken directly from the harbour.More than 10.9 million people visit the Opera House every year.

The opera featured live chickens and one bird walked off the stage and landed on top of a cellist.

A net was installed above the orchestra pit in the Joan Sutherland Theatre during the 1980s following an incident during the opera Boris Godunov.

Arnold Schwarzenegger (former actor and Governor of California) won his final Mr Olympia body building title in 1980 in the Concert Hall.

Temperature and humidity are critical to musical instruments.

When the Sydney Symphony Orchestra is on stage in the Concert Hall, the temperature must be 22.5 degrees to ensure the instruments stay in tune.

She has since visited four times, most recently in 2006.

Sydney Opera House was opened by Queen Elizabeth II on 20th October, 1973.

Seven A380s could sit wing-to-wing on the site.

There are more than 1 million roof tiles covering approximately 1.62 hectares sitting over the structure.Sydney Opera House was added to UNESCO's World Heritage List in 2007.In 1960, he climbed the scaffolding and sang Ol' Man River to the construction workers as they ate lunch. Paul Robeson was the first person to perform at Sydney Opera House.Work commenced in 1959 and involved 10,000 construction workers. Construction was expected to take four years.Jørn Utzon from Denmark was announced the winner, receiving ₤5000 for his design. 233 designs were submitted for the Opera House international design competition held in 1956.The final cost was $102 million and it was largely paid for by a State Lottery. The original cost estimate to build Sydney Opera House was $7 million.Bennelong Point was named after Woollarawarre Bennelong, a senior Eora man at the time of the arrival of British colonisers in Australia in 1788. Sydney Opera House sits on Bennelong Point.

The sydney opera house