This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

A crumbling hospital from the 1850s on Roosevelt Island.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

This impressive ledge seems to float above the Upper Buffalo Wilderness.

You can dig up your own crystals in the quartz capital of the world.

The highest waterfall between the Rockies and the Appalachian Mountains.

The warmest cave in the Ozarks features two seemingly bottomless lakes.

Two gushing waterfalls of hot spring water within a block of each other.

These waterfalls can be twins or triplets, depending on how much it's rained recently.

This restaurant serves wood-fired fare served in a natural cave with a live spring.

Home to a seasonal waterfall and swimming hole in the Ouachita Mountains.

On the side of Arkansas' Great River Road stand the remains of a forgotten World War II POW Camp.

An abandoned early-20th-century boomtown sits within the Calico Rock city limits.

The only diamond mine in the world where you can keep what you find.

The Old Mill shown in the opening credits of “Gone With the Wind” is actually fairly new, and was never a mill at all.

A World War II-era submarine is stuck in the mud in New Jersey.

A giant scrap metal troll rests his hands on top of a dilapidated building covered in graffiti.

This stone bridge is all that remains of a submerged New Jersey town.

Randy Senna's Fascination and retro arcade is home to the last Fascination game in New Jersey, and one of seven remaining as of 2021.

These unassuming lighthouses have seen the first reading of the Pledge of Allegiance, the first wireless transmission, and more than one mystery.

Rusting away on the edge of New Jersey are the remains of a Cold War missile launch site.

The rusting remains are visible sticking out of the waters of the Delaware Bay.

The only thing better than tubing down New Jersey's scenic Delaware River is doing so while eating a hot dog from a giant floating stand.

Destructive children, start your engines.