This Polish cave has housed a dragon, a brothel, and an enduring legend.

This Nazi ruin was the site where Hitler was almost blown up by a suitcase bomb.

Real bones which are said to have belonged to a Polish dragon.

An underground city of salt.

High winds can make this one scary landing.

Highly spherical boulders on the shores of New Zealand.

One of the world's steepest streets seems to have houses sliding down it.

Running since 1864, this clock has yet to be wound, one of the longest-running science experiments known.

One of New Zealand’s few castles boasts beautiful gardens, grand architecture, and a history filled with family drama.

Known for the tunnel that leads visitors to the water.

A perfect turquoise lake colored with glacier dust.

A giant doughnut was given to the small New Zealand town of Springfield to promote "The Simpsons Movie."

The "punniest place on Earth” has nearly as many bull-themed puns as it does people.

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

Some of the clearest water anywhere in the world.

Anyone wanting to know what a dwarven mine sounds like need only visit the tunnels of this New Zealand artillery compound.

When life gave this firefighter a forest fire, he made a rough-hewn sculpture park using a chainsaw.

The installation’s official name, “You Who Are Getting Obliterated in the Dancing Swarm of Fireflies,” says it all.

A flooded Mexican cave that hides a river beneath the water.

Every equinox this Maya pyramid puts on a spooky ancient light show.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

This former theme park in New York's Adirondack Mountains fell into ruin before being resurrected as a state-run campground

The biggest museum dedicated to insects in North America, one of the largest in the world.

A massive Montreal stadium that has seen nothing but trouble since its inception.