The randomness of this wall of lava lamps helps encrypt up to 10 percent of the internet.

More than five miles of underground passageways.

The best Tiki bar in Las Vegas.

Ruins of a Carnegie family mansion on Cumberland Island.

The crumbling remains of a 19th century fortess.

This road in the Great Smoky Mountains was supposed to assuage a displaced community, but ended up a $52 million dead end.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

Ancestral Puebloan ruins, natural arches, and box canyons abound in this seldom-visited corner of Monument Valley Navajo Tribal Park.

The unbelievably opulent home built for an infamous newspaperman.

A hidden subterranean installation offers a view of the sky.

This home is decked out like a psychedelic explosion of colors and bowling balls.

Acres of natural wonders left behind by a socialite-turned-gardener.

The longest continuous lava tube in Oregon.

An extraordinarily ornate museum in San Diego holds wondrous anthropological treasures.

A multi-storied adobe complex has been inhabited for more than a thousand years.

The second largest waterfall by volume in the U.S., Willamette Falls is outdone only by Niagara in the amount of water that is pushed northward.

Stroll the grounds built by murder, suicide, and dirty oil money at one of Hollywood's most filmed mansions.

Love, knishes, and best wishes from this legendary Lower East Side bakery.

A century-old hotspot for jazz, frequented by everyone from Charlie Chaplin to Al Capone.

By day this New Orleans square is for pedestrians, but by night it is a kingdom of kittens.

Hundreds of trees made from glass bottles make up this forest on Route 66.

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 artist James Turrell is repurposing an extinct volcano crater as an observatory to experience the cosmos.

Abandoned power station once home to a squatter community, now being developed into an arts center.