What are some of the most popular tourist attractions to visit in Sydney?

Sydney has many famous landmarks and attractions, with the most famous being the Sydney Harbour Bridge and the Sydney Opera House, situated on the foreshore of Sydney harbour. These two landmarks are the iconic images of Sydney and are often viewed from public ferries, either a ferry taken to visit Manly Beach or to Watsons bay. Visitors to Sydney also often visit the historical Rocks district to see the oldest surviving buildings in the city and learn about the town's early history. The view from the top of the Sydney Tower is also popular, with views out to the Pacific Ocean over the famous Bondi Beach. Also located on Sydney harbour is the Taronga Park Zoo, with animals both domestic and imported and a spectacular view over the harbour. Further out of town it is common to visit the Blue Mountains, with the Three Sisters rock formation at Katoomba being particularly popular.