An abandoned, unfinished mansion on grounds strewn with lava rocks.

Once the gateway to the utopian dream-village of a Civil War embalmer.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

A free, public museum dedicated to the fascinating science of sight.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

Only hotel where you can legally launder money.

Furniture tries to escape an abandoned building in San Francisco.

This odd California folly seems like it was almost designed to accumulate urban legends.

A psychedelic labyrinth on the San Francisco bay.

The world's first permanently occupied mountain-top observatory continues to report on the stars.

A playground built by the kids that is a child's wonderland, and a helicopter parent's nightmare.

Abandoned landscape once home to "the world's largest winery."

Hidden beneath a lake for decades, this brutalist mine has now emerged from beneath the receding waters.

A store that sells all manner of bones, insects, and animal curiosities.

9,000 square feet of vintage and modern mechanical toys, dioramas & sideshow curiosities.

Location of the most powerful laser in the world, and the potential birthplace of tiny stars.

Travelers exchange letters with woodland creatures at this mini post office.

A breathtaking 19th-century trail overlooks Lake Tahoe.

This historic estate on the east shore of Lake Tahoe was home to an eccentric millionaire (and his pet elephant, Mingo).

A tribute to the life and work of the beloved "Peanuts" cartoonist.

A sparse, solitary sequoia still stands as a living tribute to the famous conservationist who planted it—but it's dying.

Junkbots and mud babies are the masterpieces in this fantastically sci-fi art museum.

The perfect spot for a picnic, right next to a giant ballistic missile.

The haunting ruins of Jack London's dream house.