One of the most photographed buildings in a city known for its Modernista architecture is an abandoned squat.

One of the world’s largest collections of petroglyphs records 2,000 years of human activity.

An abandoned colonial French prison notorious for its hellish conditions.

An iconic red telephone box turned tiny art gallery.

This eatery transports diners to a place that no longer exists: East Germany.

Hidden deep within a Filipino jungle is an incredible waterfall that plunges into a dazzling blue-green pool.

It celebrates a very stinky task and salutes London's fatberg-vanquishing team.

Ride a boat through this magnificent underground world, which now doubles as a theater.

This grand manse has been transformed into a museum devoted to one of the founders of Fantastic Realism.

A fire station-turned-church-turned-museum dedicated to the work of seminal light artist Dan Flavin.

This hidden alley near the location of Rome's first theater was the site of a curious miracle.

Once one of the largest rooms full of books in the world, this bookstore basement is still a treat for bibliophiles.

You don't have to be an ambassador to dine like one.

A galley-shaped memorial to the prisoners of an infamous fortress.

An amazing collection of curiosities hidden in a small Welsh village.

The tallest statue in Italy is also one of the world's tallest statues of Jesus.

This Turkish cave boasts some rather bizarre associations with the King of Mount Olympus.

This church carved into the rocks is full of enchanting stone statues.

At the right time of day, sunlight floods through the roof of this cave and illuminates the small pavilion hidden within.

This recessed garden protects thousands of mountain plants by creating its own microclimates.

Flames have been burning within this mountain for more than 2,500 years.

A lavish 16th-century mansion filled with spectacular staircases, fantastic frescoes, and gorgeous gardens.

England's most famous front door has an accidental doppelganger.

These ruins of a medieval church are full of architectural mysteries.