When ecosystems collide in the arid Southwest.

A fiery crater has been burning in the Karakum Desert since 1971.

The highest bridge in America was built for an almost unnervingly small amount of money.

A museum dedicated to the history of a terrifying secret police is now held in their former headquarters.

After starting as a whimsical tourist attraction that eventually found its way to ruin, these renovated canals offer a lush and exotic locale on the Pacific Coast.

One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

Rebuilt remains of a temple to Roman god Mithras.

Northern Ireland's Brobdingnagian stepping stones.

The fountain marks the area where hundreds of accused witches were burned at the stake.

The magic's in the hole!

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

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

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

The atmospheric road was never meant to be so creepy.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

Macabre astrological automaton clock dating to the late 1400s.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

Odd outsider art installations surround a Gold Rush-era ghost town.

A beautiful geyser under environmental threat.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.