Hidden behind a wall, Spanish nuns distribute their signature sweets on a revolving tray.

The little church's beautifully frescoed ceiling has earned it the nickname “the Sistine Chapel of Madrid.”

The world's largest wooden structure.

The only urban monument in the world designed by the great surrealist painter Salvador Dalí.

Natural stone arches form a walkable "cathedral" at low tide, then disappear entirely when the water returns.

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

The studio of Catalonia's most famous theatrical designer remains exactly as he left it.

The morbid items in this small and hidden museum are not for the weak stomached.

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

A whimsical brother of the nearby Fallen Angel statue takes the falling part quite literally.

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

A temple to modernity, tucked away amid Barcelona's more well known museums.

Abandoned for decades, trains still pass through the now-restored remains of one of Madrid's first metro stations.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

This semi-secret storybook hedge maze is also the oldest garden in the city.

Old batteries and frog skeletons reside in this lakeside monument to Alessandro Volta.

This 1st-century CE Roman bath sits under a carpark.

The abandoned "Ghost Mansion" was left to decay in the mountains of Northern Italy.

An unusual resting place built into the hill with an amazing view of Lake Como.

This Ecuadorian cemetery is home to a jaw-dropping topiary wonderland.

One of the world's tallest waterfalls wasn't revealed to the world at large until 2006.

Tokyo’s only Vaudeville-cuckoo clock–steampunk-Victorian curio cabinet time piece.

This subterranean spot might be the epitome of Japan's baroque, retro coffee houses.