Take a tour of the world-famous Sydney Opera House. There are a handful of options (including an intimate backstage tour), held throughout the day. Of course, schedule permitting, travelers can also take in a show.
The best way to see the harbor is to get a bird's-eye view from the top of the Harbour Bridge on a Sydney Harbour Bridge Climb -- not your ordinary stroll across a bridge and not just for the young and crazy. The 3.5-hour trek up and down the famous landmark is safe, slow and suitable for people of all ages and fitness levels; you'll don a harness. Also available are an Express Climb, which takes only two hours and 15 minutes, and a Sampler, which takes you to a vantage point halfway up in an hour and a half.
The climbs are guided tours and are offered during the day as well as at night. There are lots of rules and regulations, including: no kids under 8 (and children aged 8 to 15 must be accompanied by an adult), no women more than 24 weeks pregnant, climbers must wear rubber soled shoes, and all climbers must pass a breath-test (for a blood alcohol limit of less than 0.05).
From the bridge, visitors can walk around the inlet to tour the always-crowded Opera House. It is easy to continue from there through the Royal Botanical Garden, a collection of flowers and trees overlooking the water, where you can see some of Australia's unique flora without leaving the city.
Go for a stroll -- or take a walking tour -- through the historic Rocks, Sydney's birthplace (it dates back to the city's beginnings as a British convict colony). There are numerous historic buildings (archeological sites and the like); plus, the neighborhood is a lively one, with many shops, restaurants and bars. Today, the narrow, twisting streets are free of criminals and fun to wander through. The shops here sell every kind of Australian souvenir imaginable, but the best come from the Rocks Markets, which are full of handcrafted and unique mementoes.
Explore Darling Harbour. While one main attraction is Harbourside, a waterfront shopping and dining complex, Darling Harbour is also a nexus for tourist attractions such as the Sea Life Sydney Aquarium, the Australian National Maritime Museum and the Powerhouse Museum, which focuses on "creativity," whether through art, technology or science (see below for more details). There are also exhibitions, displays and impromptu music performances, plus numerous restaurants grouped around King Street Wharf. Also worth a visit is the Chinese Garden of Friendship, which features winding pathways, meandering waterways, and exotic flora and fauna.
Visit WILD LIFE Sydney Zoo, an exhibit of Australia's most exotic critters and plants. You may not be able to find wild koalas lounging around Sydney, but you can get up close with them at the koala sanctuary here. The park includes multiple habitats, such as the Daintree Rainforest and Wallaby Cliffs, that supply a peek into different climates and animal homes around Australia. The Sydney Aquarium is right next door, and combination ticket deals are available.
Get out on the water via Harbour Jet. It's not for the faint of heart -- the speedboat ride offers some commentary, but the real fun is in the 270-degree spins, wild fishtails and other boat-acrobatic maneuvers. Captain Cook Cruises offers a gentler ride.
See Sydney from above on a helicopter tour (offered by several companies, including Blue Sky Helicopters). They offer views of Sydney's entire extensive coastline, as well as the harbour, the city and even the Blue Mountains out to the west.
Check out Sydney's art scene with a visit to the edgy Museum of Contemporary Art Australia. The Art Gallery of New South Wales features a wide range of art, including Australian, Aboriginal, Western and Asian exhibits.Photos: 11 Best Australia Experiences
A slightly different kind of museum is the Powerhouse, which is devoted to celebrating outstanding technology and design. An old power station in the former industrial district of Ultimo has been converted into a museum that hosts continuously changing exhibitions (topics have ranged from Sherlock Holmes to the evolution of the human voice).
Explore King's Cross, Sydney's infamous red light district. This once-bohemian town is in the process of gentrifying into one boasting fancy bars and upscale apartments, at least on the outskirts of the neighborhood. Take a walking tour with Viator to catch a glimpse of the area's seedy, sometimes sordid and always fascinating history.
Barangaroo is a new waterfront park, part of a larger urban renewal project that will eventually include cultural spaces, restaurants, cafes and shops. For now visitors can hike or bike amid native plants, or take an Aboriginal culture tour.
Rent a car or hop on one of the bus tours that leave from Sydney and go wine tasting in Hunter Valley (a two-hour drive from Sydney), which features some 50 wineries. Boutique Tours Australia will take you from Sydney to the valley for private tastings at some of the region's best wineries. Viator also offers a number of wine tours.
If you have a couple of days to spare, drive out to the Blue Mountains, where draws include beautiful scenery, bushwalking, rain forests, waterfalls, a scenic railway and more. The area is an hour and a half by car from Sydney. It's also a very romantic destination with lots of intimate inns. Check out Blue Mountains excursions from Viator.
Hit the beach! Manly, accessible via a 35-minute ferry ride from Circular Quay, offers scenic walking, water sports ranging from windsurfing to parasailing, and numerous cafes and restaurants. Bondi Beach (reachable by bus from Circular Quay) is Australia's best-known beach, with lots of restaurants, shops and cafes. It's also the most crowded strip of sand in Sydney. Be aware that topless sunbathing is accepted.
A hiking path cuts through the cliffs between Bondi and Coogee, another beach suburb several miles south. The walk can be strenuous, but the views of the seemingly endless Pacific Ocean from the top of the cliffs are unbeatable, and there are several other beaches to make rest stops at along the way for a refreshing drink or swim.
Editor's Note: IndependentTraveler.com is published by The Independent Traveler, Inc., a subsidiary of TripAdvisor, Inc., which also owns Viator.
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