This striking arch, one of the first architectural elements constructed in Prospect Park, was recently restored to its original glory.

Tucked away on a scenic trail, a modest memorial honors one of the greatest writers of our time.

This desert oddity hides in plain sight thanks to a cartographic error and a desert explorer with a punny sense of humor.

Manhattan's Thirteenth Avenue was made on landfill then deliberately destroyed — apart from one small, obscure block.

The former home is said to be haunted by the ghosts of the beloved mayor and his wife who lived here.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

The farm where one of America's greatest leaders was raised is now a well-appointed landmark.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

China's very own Atlantis is an ornate dynastic city resting at the bottom of a lake.

A huge musical instrument played by the ocean.

Deep under Manhattan is the largest construction project in city history. So far, the project has taken the lives of 23 workers, or "a man a mile."

The bullet-riddled wall from the St. Valentine's Day Massacre, bloodstains enhanced for your viewing pleasure.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

A battle between nature and architecture in the Cambodian jungle.

The only structure left with direct ties to the Salem witchcraft trials of 1692.