An underground city of salt.

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

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

Dolphins, ancient clams and hundreds of waterfalls make this one of the world's top tourist destinations.

This strange geological landscape erupts with sudden bursts of water.

After the devastating 2011 earthquake, historic Christchurch begins to recover, starting with the pop-up Re:START mall.

Pilgrimage site for star-crossed lovers.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

The famous sculptor left his mark on this Italian wall in an internationally protected example of street art.

Italian poet Dante Alighieri is entombed in this small mausoleum in Ravenna, and his hometown of Florence has never been too happy about it.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

An exquisite collection of fairytale conveyances that puts most car museums to shame.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

"In the Dark" Restaurant in Paris offers dinner in complete darkness.

A New Zealand couple's shell-adorned home living room, now on display at the Canterbury Museum.

New Zealand's epic shrine to all things puzzling.

A perfect turquoise lake colored with glacier dust.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A museum dedicated to a Cold War era sausage.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

The history and future of cannabis.

Cat art as far as the eye can see.