A slide-show essay on Seattle's floating dome, Edmonton's Omniplex, and other great unbuilt stadiums.

In 1970, construction began on Seattle's Kingdome. Thirty years later, the 55,000 seat stadium was destroyed. Its implosion, the largest demolition of its kind in recorded history, was a national event, broadcast live on ESPN Classic. You can still buy Kingdome implosion memorabilia in Seattle gift shops.

With the Kingdome now reduced to rubble, it's easy to forget that the enormous stadium almost never existed. In the early 1960s, when Seattle first considered building a multi-sport stadium, there was a far more alluring plan on the table. Designers proposed a floating, retractable-roof stadium that would have sat in Elliott Bay just west of Seattle Center—home of the Space Needle and the 1962 World's Fair.

There is little doubt that such a stadium, if constructed, would've become the icon that the characterless Kingdome never was. While the stadiums we erect can embody both civic pride and civic catastrophe, unbuilt stadiums reflect our ambitions and our shortcomings more brightly. The ballparks we imagine, design, and fail to see through to completion are testaments to our egos, our metropolitan insecurities, our ever-changing sense of aesthetics, and our growing economic expectations.

Launch a slide-show essay on North America's unbuilt stadiums.