No architectural structure stands out as a symbol of the city more than the Sydney Opera House. The performing arts center is one of the 20th century's most distinctive buildings as well as a UNESCO World Heritage site. It lies just off Sydney's central business district and adjacent to the Royal Botanic Gardens (sydneyoperahouse.com).
The Sydney Harbour Bridge is the city's oldest landmark. Together, the bridge and the nearby opera house provide one of the world's most distinctive views — from any direction. Adventurous travelers can pay to climb the bridge day or night on guided tours. A less extravagant option is to use the pedestrian walkway (harbourbridge.com.au).
Numerous tours are available to the Blue Mountains. The Mountains are a deep blue-green panorama of eucalyptus trees (bluemountains.com.au). Guides provide insight into the unusual plants that thrive in hot, dry conditions. I like Sydney Great Escapes for their smaller groups and great guides (sydneygreatescapes.com/tours.html). Many of the tours stop at Featherdale Wildlife Park, where you can pet a cranky koala, hand-feed the friendly wallabys, see kookaburras, dingoes, Tasmanian devils, kangaroos and the most colorful birds in the world (featherdale.com.au).
The Circular Quay (pronounced key) is the center of the business district and a prime tourist stop. The hop-on-hop-off tourist buses start here several times an hour. They're great for a first-day overview of the city.
The Rocks Markets, a block or two from the Circular Quay, are a collection of open-air markets for food and crafts with live music in the neighborhood known as the Rocks. Check the schedules for hours (therocks.com).
The Taronga Zoo sits a 15-minute ferry ride across the harbor from the Opera House. The ride alone provides some of the best views of the city. The modern zoo with lush habitats is built into the side of a cliff so a tour resembles a nature walk. Don't miss the Barbary sheep (taronga.org.au/taronga-zoo).
Ride the Harbour City Ferries. Jump off at Manly and spend a day at the beaches or disembark at Watsons Bay to to see the suicide cliffs and get some ice cream (transport.nsw.gov.au/customers/ferries/sydney-ferries).