Abandoned for over a century, this chilling train tunnel is now a destination for ghost hunters.

Phil Mortillaro uses keys to bring art back to the Village.

The former sign of this immortal music venue is just that--undying.

Slyly buy a shake in the Parker Meridien lobby.

Once considered the height of medical modernity, this structure is now the oldest remaining component of Roosevelt Hospital.

One of the last full-orchestra recording studios in New York City and an acoustical marvel.

Where Venice's gondolas go for a tune-up.

It's said this geological anomaly was caused when the Devil took a bite out of the Irish mountainside.

A teddy bear sits on a chair watching the sunset from the mountaintop—just as the late Dan Clancy had done since childhood.

After it was swallowed by a Georgian mansion, this medieval castle remained forgotten for centuries.

This 5,300-year-old tomb with mysterious carvings crowns an Irish mountain.

The enchanting archway is the only surviving portal into Dublin's lost medieval wall.

The ancient tomb acts as a calendar that keeps perfect time.

Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

An important pilgrimage site for pagans and early Christians, named for a Celtic goddess-turned-saint.

The oldest public library in Ireland.

An eccentric garden of sculptures crafted in India decorate an Irish green space dedicated to Alan Turing.

An Irish town has built a statue to a silent film actor simply thanks to the holidays he once spent there.

A museum that cashes in on its infamous little people while teaching you a thing or two about the Irish fey.

The taxidermy remains of the most popular pony in children's literature.

A castle inspired by medieval architecture is hidden in the woods of Connecticut.

The ghost town that was one of New Hampshire's first settlements now exists as a park detailing its history.

Around 100 sculptures from artists all over the world decorate the hiking trails surrounding this locale.

The largest arcade museum in the world chronicles the golden age of video games which ended promptly in 1987.