The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

A serpentine highway twists and turns over the treacherous Norwegian Sea.

Thousands of exquisitely carved stone water storage wells, hundreds of stone steps fill this exquisite medieval stepwell.

This abandoned amusement park was built on a site with a dark history.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

Stunning wetlands ablaze with pink lotus flowers.

This volcanic cave lake is essentially hard proof that Iceland is the most magical place on Earth.

This shop for all your super spy needs hides an educational secret.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

Ruins of a German Castle on top of a towering stone pillar.

A winding path built in secret on the edge of the continent.

One of the world's oldest and most massive living organisms is a grove of quaking aspens.

Mysterious rocks that ring musically when struck.

The oldest stone house in Paris was built by its most famous alchemist.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

The atmospheric road was never meant to be so creepy.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

The first declared National Monument in the United States.

Northern Ireland's Brobdingnagian stepping stones.

Stroll through a wonderland of stupendous moss-covered trees.

France's most famous cemetery, with some of its most curious tombs.

The United States Capitol's former columns still stand.

A strange house built only at night, with rumored mystic inspiration.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.