An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

A fairytale-like medieval church perched atop a rocky cliff on Italy's "Coast of the Gods."

A sulfuric hellscape in southern Italy.

A mud volcano in Indonesia spews out 50,000 cubic meters of mud every day.

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

Medicinal spa created with the discharge from a geothermal energy plant.

Most-visited and most-photographed slot canyon in the American Southwest.

A lovers' beach, tucked below the surface of the island, provides a safe haven for romance.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

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

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

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

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

This city square is home to Amsterdam's oldest church and a statue honoring Dutch sex workers.

Banksy gives themself artistic license with this piece of London street art.

This collection of illusory paraphernalia has been culled from the history of London's premier magician's club.

A 2000-year-old Roman amphitheater lies just below Guildhall Yard.

This miniature take on the Kremlin is one Dutch man's retirement project.

Devious political maneuvering and four ancient, working telescopes are central to the world's second-oldest observatory.

The works of poetry's biggest names grace the walls of the city of Leiden, all carefully painted by hand.

This historic Amsterdam bar used to accept sailor's monkeys as payment.

The attic of a four-century-old canal house hides a clandestine church.

Museum preserving torture methods from the past.