Bold black and white motifs of life and death add a dramatic flair to this 17th-century crypt.

Partially collapsed lava tube and cave system complete with concert hall, underground pond, and unique albino crabs.

A Spanish forest is filled with mysterious stone carvings.

Bacteria and algae give the salty water its bubblegum hue.

Cliffside houses provide a spectacular view from their perch above the valley.

At the foot of a waterfall lies a peaceful swimming lagoon and evidence of over 60,000 years of human habitation.

An isolated village literally built into the crevices and rock formations of a mountain.

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

Spanning the El Chorro gorge, this pathway used to be one of the most dangerous crossings in the world.

Wonderland replication in progress by one persistent man.

Hundreds of stone stairs and a winding medieval bridge connect this haunting Spanish island to the mainland.

An enchanting monastery in the Spanish countryside appears lifted from a fantasy tale.

Three bridges and one giant canyon make up this fantastic Spanish settlement.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

This cemetery features modernist statues as strange as its name.

A beautiful but toxic fountain of mercury.

An 11th-century fortress home to one of the most influential royal houses in medieval Europe.

A symbol of friendship between the mountainous regions of Switzerland and Bhutan.

Museum dedicated to wax representations of disfiguring diseases.

Enormous, fluffy dogs frolic around this museum dedicated to a legendary Saint Bernard.

For centuries no one knew there were hundreds of bones and precious artwork hidden beneath this Swiss church.

Traversing steep Alpine slopes, this engineering marvel is one of the longest and highest funiculars in the world.

The steepest classic funicular in the world glides along a dizzying incline.

This 170-year-old Swiss guesthouse built into the side of a mountain is best accessed by a cable car.