Venice's "Island of the Mad."

This fantastical waterfall is hidden in a cave located in a cracked cliff.

A rococo room covered entirely in porcelain originally constructed for another royal residence.

This shining multicolored metro station deep under Naples is said to be the most beautiful in Europe.

Skulls from the plague of 1656 and World War II bombings are united by a cult dedicated to caring for the ancient dead.

This dreamlike museum is filled with the works of an influential surrealist artist whose name you may have never heard.

This museum dedicated to divination also honors a local 10th-century prophetess.

This fairytale-like structure is the last turf church ever constructed in Iceland.

The largest whale museum in Europe allows visitors to walk among life-size giants.

Every summer local children form "pysja patrols" to save young birds that have wandered from their nests.

The Icelandic Sea Monster Museum explores the area's history of aquatic cryptid sightings.

An encyclopedic collection of mammal penises.

This modern monument to pagan belief looks like it was transported straight from ancient times.

Iceland's "Smoky Valley" is a beautiful river that is shrouded in a constant cover of steam clouds.

Strange rock formations tower above the river that snakes through this enchanting Icelandic canyon.

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

Staves, storm-calling, and of course, necropants.

In Lago Superiore, the largest expanse of lotus flowers outside of Asia is hard to miss.

The oldest residential street in Europe also features an optical illusion.

The titular "little arch" near this Italian resort is one of the most popular diving spots in the country.

A striped 12th-century basilica sits in the countryside of Sardinia.

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

A one-ton statue of Steve Rogers beautifies the entry to a Brooklyn Bed, Bath & Beyond.

A small window on Via Piella offers a lovely and rare peek at Bologna's lost canals.