Captain America, Sub-Mariner, and the Human Torch were all born in this art deco Manhattan masterpiece.

An isolated dive site teeming with cnidarians.

Meet the world's longest tapeworm in a collection that really gets under your skin.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

On Japan's Tashirojima Island, cats are king.

This Los Angeles animation studio is keeping the wonder of stop motion puppetry alive.

This Croatian island is for sale but no one is buying due to the dozens of accused Nazi sympathizers who were massacred there after WWII.

The "Fun Spot of the Desert" is now a haunting ruin, and a reminder that putting a water park in a desert is a bad idea.

The name of this famed hospital was once a byword for the horrors of medical and psychiatric care.

Decades after testing the polio vaccine on unwitting patients, this historic mental hospital sits in ruin.

An English artist has turned an unassuming ex-council house into a time-lost house of mystery.

After millennia of erosion by sand and churning water this Brazilian valley now looks like a lunar fantasy.

This otherwise innocuous bodega was once the headquarters of the most feared assassin's guild in American history.

This legendary "evil" doll has been haunting the citizens of Key West for over 100 years.

A massive underwater sinkhole made famous by Jacques Cousteau.

This Japanese-inspired labyrinth of hot springs is hidden in a Chilean forest.

This former Nazi castle was built as a school to train what would have been the future of the Third Reich.

The bluer than blue waters in these natural Israeli caves are reached via the world's steepest cable car.

This abandoned Civil War fortress is slowly being swallowed by the waters of Lake Borgne.

This Nazi ruin was the site where Hitler was almost blown up by a suitcase bomb.

This abandoned five-star hotel is now a five-star urban exploration destination.

This empty Detroit high school was too expensive to maintain or destroy.

The alpine falls where Sherlock Holmes apparently met his demise can actually be visited.

This massive blockhead sculpture hides an entire library.