These aggressively sustainable art homes look like something out of 1970's science fiction.

A phenomenal assembly of pueblos in New Mexico is the most complete example of ancient ruins north of the border.

The abandoned personal amusement park of the King of Pop.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

A sculpture made of 10 Cadillacs as a monument to the "Golden Age" of the American automobile.

European castle ruins in an American state park are actually the product of death and grief.

The longest living non-clonal organisms on Earth.

This natural wonder drops 16 stories straight down through rare flora and streaming waterfalls.

Sandstone rock formations that look like they belong on the cover of a progressive rock album.

The remains of an idyllic small town built for the film 'Big Fish' still stand around a rundown main street.

Giant busts of 42 U.S. presidents are sitting in a field in Virginia.

Brightly colored 30-foot-tall totems light up the desert sky just outside Las Vegas.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

An arsenic-filled pool in the Grand Canyon takes on the appearance of a giant, overflowing pumpkin.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

This abandoned Navy base was transformed into an off-grid alternative living community for thousands of people.

This geothermal hot spring hides beneath a slowly growing mineral dome.

The largest self-built castle in the U.S., six decades in the making.

Less a museum than a bizarre fantasy world created by artists and engineers.

A reproduction of earth's many biomes.

A Swedenborgian glass church surrounded by redwoods sits perched atop a massive landslide area.

An acoustic anomaly with a mysterious cause.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."