The New York hotel where tragic visionary Nikola Tesla spent his final hours, destitute and alone but for the pigeons.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

The "Seinfeld" diner.

Blighted Irish field and the ruins of a 19th-century cottage on the edge of urban Manhattan.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

Once the tallest building in the world and the site of "the highest dinner ever held in New York" this building now holds the most expensive penthouse in the city.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

Mysterious 500-year-old tapestries depict a unicorn hunt.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

New York City's smallest piece of private property.

Elevated freight railway turned wildly successful urban park.

A museum dedicated to exhibiting remarkable outsider art.

Bubbling up from deep underground is the warm crystal clear water that fills the Warm Springs Pools, America's oldest spa.

Located at the former Lorton Prison the Lucy Burns Museum tells the story of the 91 year history of the prison including the dark chapter of its involvement in the women's suffrage movement.

The romance of early commercial flight still fills this Art Deco destination.

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

A former major munitions plant that has been converted into a sprawling art space.

A convincing little bit of ancient Egypt smack dab in Richmond, Virginia.

Inspired by a foil-wrapped potato, (seriously) the Markel Building has been deemed one of the 10 ugliest buildings in the world.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

A former mental hospital founded in the 1930s by a eugenicist who advocated for the forced sterilization of patients.

The only recreation of William Shakespeare's indoor playhouse.

At 207 feet, one of the world's longest continuous escalators.