Cathedral carved out of salt, located a mile below the earth's surface.

The site of the climactic scene from the classic horror film is now a historic landmark.

At 207 feet, one of the world's longest continuous escalators.

Home to items never before seen by the public.

America's Most Wanted's set resides in this tribute to the history of crime and punishment.

This stately building in Alexandria, Virginia was built by Freemasons to honor one of their most famous members.

A former major munitions plant that has been converted into a sprawling art space.

Dentist's hated concrete colossi are now beloved icons of the community.

The first U.S. town to secede from the Union, only to vote themselves right back in.

A middle school sports field that many believe was the true location of the first successful powered flight - and not by the Wright Brothers.

The Empire Mine is "one of the oldest, largest, deepest, longest and richest gold mines in California."

The beauty and the beast of hydraulic mining is on full display at this California Historic State Park.

Singing sand that stands as the final remains of an ancient lake.

An abandoned lot littered with concrete debris was once the home of the world's first female railroad president.

A watering hole where the options for seating include a bar, patio, or subterranean cave.

Established in 1853, this crumbling cemetery sits forgotten on the corner of Church and Chapel in Gold Country.

The oldest continuously operating Catholic school west of the Mississippi.

A fine mixture of the old and the new topped with an art deco neon spire.

This massive redwood tree has a hole in the base big enough to drive through.

A trash dump made beautiful by nature's power.

World's first "penitentiary," meant to be humane, drove men insane.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.