The towering, white "Great Wheel" features 42 enclosed gondolas with space for up to 252 passengers total. The 175-foot-tall (53-metre-tall) wheel cost $20 million and was constructed as part of a private-sector initiative to revitalize Seattle's waterfront.

While the 212-foot-high (66-metre-high) Texas Star is taller, it only operates during the annual State Fair of Texas in Dallas.

Seattle's new wheel "is like a baby London Eye," said 32-year-old co-owner Kyle Griffith, referring to London's famed 443-foot-high (135-meter-high) wheel along the Thames River.

The London Eye is Europe's tallest Ferris wheel. The tallest in the world, Singapore's 541-foot (165-metre) Singapore Flyer, is more than twice as high as Seattle's newest attraction.

The Great Wheel was designed to draw visitors to the Pacific Northwest city's gritty waterfront, often framed by fog and drizzle, amid worries that a traffic-clogging construction project underway nearby would keep tourists away.

That project, a $3.1 billion, 1.7-mile (2.7-km) deep-bore tunnel, is being built to replace the Alaskan Way Viaduct, an elevated 1950s-era north-south artery. The new tunnel is scheduled to open between late 2015 and early 2016.

"Our whole idea was to create an attraction that was a neat thing to make people want to come down to the waterfront," said Griffith, vice president of Great Western Pacific Inc.

The wheel opened to the public after an afternoon ceremony attended by about 1,000 invited guests, including Mayor Mike McGinn and family of the developers.

The University of Washington's Husky Marching Band played for the crowd, and its musicians were among the first to ride the attraction.

"It's the bling that Seattle needed," said Patty Chasman, 60, after taking her first ride.

Said Anna Lynn Heine, 12, "I could see everything."

'ICON DU JOUR'

Seattle's wheel weighs more than 280,000 pounds (127 tonnes)and extends 40 feet (12 metres) over Puget Sound's Elliott Bay at Pier 57.

The pier has a storied history. A Japanese freighter docked at the location in 1896, opening trade between Seattle and Asia.

A year later, the steamship Portland arrived, bearing a "ton of gold" from northwest Canada's Klondike, thus launching an Alaska Gold Rush, as Pier 57 lore would have it.

Each enclosed gondola on the wheel is equipped with heating and air-conditioning and seats six passengers for the 12-minute, three-spin ride.

One car features a glass floor and red leather seats, and will host special-occasion dinners and cocktails, Griffith said.

Tourism officials hope the Great Wheel will lure some of Seattle's 9.9 million annual overnight visitors to its central waterfront, a 1.5-mile (2.4-km) walk from the Space Needle, the city's most famous attraction.

Globally, high-tech wheel rides are undergoing a resurgence after being out of vogue for 30 years, analyst Dennis Speigel, president of Ohio-based International Theme Park Services Inc, told Reuters.

"Wheels are now the 'icon du jour,'" Speigel said.

On Staten Island, New York, plans are in the works for a 600-foot-tall (183-metre-tall) "observation wheel" to become the world's tallest.

Two new wheels also are under discussion in Las Vegas, Speigel said. Developers broke ground on one, a 500-foot-tall (152-metre-tall) wheel in March 2011 across from the Mandalay Bay resort and casino.

Another opened in South Carolina's Myrtle Beach last year.

"Overseas, they're all getting taller and taller. In the next 10 years we'll see a 1,000-foot-high (300-metre-high) wheel," Speigel said. (Editing by Mary Slosson, Steve Gorman and Mohammad Zargham)

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