These towering spires and glowing walls are carefully crafted from hundreds of thousands of icicles.

Even Henry David Thoreau found this glacial pothole irresistible.

This narrow canyon has been carved by the river over thousands of years into spectacular and curious forms.

Not one, but two of Frank Lloyd Wright's architectural masterpieces nestled on the same street.

The largest arcade museum in the world chronicles the golden age of video games which ended promptly in 1987.

Fortified homes of highland warriors that are still in use today.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.

A marvel of Byzantine engineering under the streets of Istanbul.

Eons ago, a rushing lava river formed this pristine passage through solid rock.

Stroll through a wonderland of stupendous moss-covered trees.

The remains of an early 1900s dude ranch that operated until the 1970s.

In the depths of the Everglades, one man has dedicated his life to studying the elusive Skunk Ape.

Steep canyon walls hide a forested oasis in the West Texas desert.

When this test site was abandoned, they didn't even bother to take the rocket with them.

This angular Dwarven tunnel cuts through a mountainside in Glacier National Park.

A memorial to the unknown and unheralded men and women of the Cold War military and intelligence services.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

This hunter-gatherer architecture is believed to be the oldest religious complex known.

The ancient tomb acts as a calendar that keeps perfect time.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

An ancient iron pillar in Delhi that seems to be rustproof.

The meteor that sealed the fate of the dinosaurs landed at this site, one of the largest impact craters in the world.

The longest living non-clonal organisms on Earth.

Native Americans built this circle of stones, which was used to predict astronomical events.