Volcanically heated hot springs.

Siddhartha Gautama sat here and received enlightenment.

Known as the leaning temple, the sacred structure has somehow developed a severe nine-degree slant.

One of the largest Buddhist stupas in the world keeps an eye out in every direction.

Sacred Buddhist home of some spiritual monkeys.

Tiny memorials honor individual victims of the Holocaust.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

Commonly acknowledged as the only public monument to the Devil himself.

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

An ancient Egyptian temple in the middle of Madrid, Spain.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

Possibly the oldest church in Barcelona, this basilica has its pagan and Christian mythologies all mixed up.

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

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

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

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

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

Sky ships, planes, and portraits left as unique tokens of hope and thankfulness.

Lyon's miniature version of the Eiffel Tower was built as a statement in support of French secularism.

For hundreds of years, automatons moving to metallic music have been marking the passage of time.

A wall of chewing gum moonlights as collective art.