3. Cape Hatteras Lighthouse (4,830 tons)

The Cape Hatteras Lighthouse on the Outer Banks of North Carolina may not be a traditional structure the way some of the others on this list are, but how could we leave out what came to be known as the "Move of the Millennium?"

Cape Hatteras lighthouse move
John Althouse/AFP/Getty Images
The Cape Hatteras Lighthouse slowly made its way to
safer ground.

The coastline was disappearing, leaving some people to fear that the tallest lighthouse in the nation would be lost to the encroaching Atlantic Ocean. The lighthouse, which was 129 years old at the time of the move, posed a special challenge because it had no internal structural supports to hold it together during the move. Though the National Park Service approved $12 million to move the structure [source: Clarke], many citizens didn't think the job could be done. The project even faced a last-minute injunction to stop the move.

Apprehensive crowds showed up to watch as the lighthouse, mounted on a foundation of 400 tons of steel -- made up by hydraulic jacks and steel beams -- edged its way down a metal runway [source: Clarke]. It took hydraulic rams 45 seconds to a minute to push the lighthouse 5 feet (1.5 meters), and the entire move took 23 days [source: Clarke]. The team behind moving Cape Hatteras was rewarded with the Opal Award from the American Society of Civil Engineers, which is the equivalent of an Oscar to an engineer.

What move tipped the scales at more than 7,000 tons? Find out on the next page.