Built on Heart Island in New York during the early 20th century, Boldt Castle was meant to be the ultimate expression of love. But it all ended in heartbreak.

Built in 1905 by eccentric sewing machine magnate Frederick Bourne, Singer Castle looms over Dark Island like a modern medieval fortress.

Utagawa Hiroshige was such a talented artist that he inspired Van Gogh and Monet. But in 1856, the famous woodblock printer "retired from the world" to become a Buddhist monk.

Known as the "father of remote control," John Hays Hammond Jr. built his dream palace with traditional medieval features, including a drawbridge, bell tower, and dungeon.

Though it has been left largely uninhabited since the 18th century, the towering Hohenzollern Castle remains one of Germany's most visited palaces for its fairytale views.

Hundreds of nearly-identical castles appear to be copied and pasted onto this Turkish hillside — but not a soul lives there.

The Sossusvlei is an ancient salt pan in Namibia's Namib Desert that transforms into an oasis once or twice every decade.

Each winter, trees piled high with snow are sculpted by icy Siberian winds into magnificent humanoid figures.

"There is a frantic race to merchandise tinsel and trash under the guise of 'modernism,'" Loewy once said. "I can claim to have made the daily life of the 20th Century more beautiful."

From innocent lingerie modeling to fetish and S&M photoshoots, these pinup girls broke the mold in 20th-century America.

In mid-century America, streamliners were luxury train cars that were supposed to herald in the future of transportation, so what happened to them?