Sydney Harbor Bridge (Sydney, Australia)

Sydney Harbor Bridge (Sydney, Australia)

While Sydney is best known for its iconic opera house and beautiful beaches, the city's top tourist attraction is a close-up, high level inspection of Sydney Harbour Bridge, which links the city's two downtown districts. In the late 1980s, entrepreneur Paul Cave came up with a novel plan to build an infrastructure that allows visitors to climb the outside of the bridge's steel superstructure to the very top, 500 feet above the water in the middle of Sydney Harbor.

In 1998, about 10 years after Cave floated his idea, the first climbers stepped out onto the harbor bridge's spidery steel spans. Since then, 2.75 million climbers have completed the Sydney BridgeClimb.

Clad in camouflaging gray and blue jumpsuits (so as not to distract drivers on the bridge roadbed below), climbers latch onto a continuous steel safety cable that winds up and down a series of ladders, mesh metal walkways, and stairs. A guide provides commentary to climbers via headphones traversing the top of the riveted iron girders that support the automobile and train roadbed below.

True, the experience is not for the gumptionless: There are about 1,500 steps to climb as well as four sets of vertical iron ladders, several low-overhead and narrow catwalks, and the possibility of exposure to hot sun and hard rain. But, planning is key, and all climbers are carefully provided with information and equipment before setting off with their guide.

Acrophobes may find the experience daunting, but everyone else will find the climb exhilarating. Marching in single file up to the summit of the bridge, climbers revel in the spectacular view of Sydney, from the Pacific Ocean to the east to the Blue Mountains silhouetting the western horizon. After the climb, you'll have no trouble finding a place to drink a celebratory Victoria Bitter or Tooheys lager in Sydney's nearby entertainment district known as "The Rocks." [From $198 Australian dollars, about $204, U.S., bridgeclimb.com]