Name the significant landmark in Sydney that is also an opera house.

The Sydney Opera House is an iconic architectural landmark and a prominent cultural site located in Sydney, Australia. It is famous for its unique shell-like design and is renowned as one of the most recognizable buildings in the world. Opened in 1973, the Opera House serves not only as a venue for performances, including opera, ballet, and theater, but also as a symbol of Sydney and Australian identity.

The design was conceived by Danish architect Jørn Utzon, who won the design competition in 1957. The building's innovative structures and use of materials make it a masterpiece of modern architecture. The Opera House hosts a variety of performances and events and is a major tourist attraction, drawing millions of visitors each year who come to marvel at its design and attend its events.

In contrast, while the Sydney Tower is notable for its height and views of the city, and the Harbour Bridge is famous for its engineering and provides access across the harbor, they do not carry the same cultural significance or global recognition as the Sydney Opera House. The Royal Botanic Garden offers beautiful landscapes and plant collections but does not serve as a performance venue like the Opera House does.