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

The installation’s official name, “You Who Are Getting Obliterated in the Dancing Swarm of Fireflies,” says it all.

Dramatic river bend surrounds a natural red-rocked pedestal.

These fantastically named natural pools look like something out of a Scottish myth.

A snapshot of the city's fascinating voodoo culture.

On Japan's Tashirojima Island, cats are king.

The sound of swaying stalks in this stunning grove has been named a governmentally recognized sound.

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

An exquisite tunnel of cascading flowers.

A magical place that lets you play in and explore the world of Studio Ghibli.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

Rippling sand dunes frozen in the Arizona rock.

A psychedelic labyrinth on the San Francisco bay.

An artsy hidden staircase leads to breathtaking views of San Francisco.

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

This colorful but controversial ceiling has been likened to a 21st-century Sistine Chapel.

One of Antoni Gaudí's least-visited works, an homage to Catalan patrimony that mixes neo-Gothic with Modernista forms.

The best-preserved ancient theater in the world.

A replica of the beloved character's house, modeled after the author's own drawings.

Mythical beasts symbolizing the city of Tokyo guard a historic bridge.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

The townhouse where the "Blood Countess" Elizabeth Báthory started her murderous career.

A spherical "micro-nation" in the heart of Vienna.

The final resting place for the remains of 143 Habsburg royalty.