An engineering error ensured this cavernous 350-foot-long subterranean thoroughfare was never used as intended.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

Achill's most recently abandoned village dates back to to the Age of Enlightenment.

The remains of a concrete ship sit on a sandbank between Ballina Quay and Belleek Woods.

Handcrafted thermal spa washes away each night with the tide.

An immersive Māori village where you can learn history and heritage through dance, ceremony, song, architecture, and food.

Major tourist destination known for its bubbling mud-pools and hot thermal springs.

These two delightful animal-shaped buildings host a visitor center and wool shop.

The real life Hobbiton, this sheep farm has been forever transformed since being built for The Hobbit film series.

Tubing through a cave lit with glowworms is a magical underground experience.

The "Rocky Horror Picture Show" character has a hidden camera that broadcasts people doing the "Time Warp."

A fitting attraction for the corn capital of the world.

A striking sculpture built to honor the women of the Lakota and Dakota Nations.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

A former imperial sea-fortress and Soviet prison.

This irregularly shaped sea fortress has defended not one but three different sovereign states.

Finland's oldest astronomical observatory once played a crucial role in seafaring and timekeeping.

An abstract monument to a symphonic composer.

A subterranean house of worship carved right out of the bedrock.

Roughly 17 million letters to Santa have found their way to this Arctic Circle post office.

If you visit Santa's village, you can get your passport stamped to show you crossed into the Arctic Circle.

This stately estate house features a tower covered in a bright, modern mural.

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

This pub can leave even the sober feeling slightly unsteady.