This isn't your average roadway—it's actually a National Park and a transportation pioneer.

The Pentagon sits on a former island that was in Virginia at low tide and D.C. at high tide.

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

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

The world-record holder for the longest bridge stretching continuously over water.

The magic's in the hole!

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

A modern mechanical planetary system, part of a 10,000 year clock.

Olfactory delights in San Francisco's Botanical Gardens.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

One of the most scenic stretches of road in America winds between some of the country's oldest trees.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

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

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

Golden Gate Park's historic collection of plants.

This tea house was a hand-built gift from Boulder's sister city in Tajikstan.

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

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.

See massive fossils that are over 200 million years old in northeastern Arizona.

One of the world's largest model railroads is a mind-boggling achievement.

This historic old movie house was the scene of one of the Blob's most iconic attacks.

What began as an art installation is now the private drinkhaüs for a brewery's employees.