Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

A mud statue stands in the dark tunnels, seeming to hold up the weight of the city above.

1920's reinforced concrete church by architect Auguste Perret changes the face of modern design.

A total of 22 tiny bridges cross this canal of the Yvette River, forming a unique trail.

This futuristic airport terminal was abandoned for decades before reopening as a hotel—with a vintage plane of its own parked out back.

20-foot tall lamp mumbles Swedish to celebrate the holidays.

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

In the middle of the desert, miles from any human life, sat an anomalous pay phone that still magically answers your calls.

It's unclear what caused the fire that led to this opulent hotel's demise.

This restaurant has been a haven for D.C.'s LGBTQ community since the 1950s.

Art deco landmark on the outskirts of Washington, D.C.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

Sit where JFK proposed to Jackie or where Nixon dined on meatloaf at this storied pub.

A historic ruin just 20 feet away from a busy highway onramp.

Mysterious installations bring levity and light to a sometimes stodgy city.

One man's swirling six-acre monument of stone.

An enormous cat made of recycled wood scraps.

A nearly 100-year-old dining car in upstate New York embodies the golden age of roadside dining.

This Central New York ghost town was once a prosperous railroad community.

At this small shop off a dirt road in the forest, the specialty is eel the owner caught and smoked himself.

The rustic think-space of famed naturalist John Burroughs stands exactly as he left it.

The world's largest kaleidoscope, designed by a 1960s psychedelic artist.

Although built to generate electricity for Marylanders, this dam has become an all-you-can-eat buffet for American bald eagles.