The Coral Castle
How did Ed Leedskalnin build the massive Coral Castle in Homestead, Florida, out of giant chunks of coral weighing up to 30 tons each with no heavy equipment and no outside help? Theories abound, including anti-gravity devices, magnetic resonance and alien technology, but the answer may never be known. Leedskalnin died in 1951 without any written plans or clues as to his techniques. The centerpiece of the castle, which is now a museum open to the public, is a nine-ton gate that used to move with light pressure from one finger. After the gate's bearings wore out in the 1980s, a crew of five took more than two weeks to fix it, although they never did get it to work as effortlessly as Leedskalnin's original masterpiece.