The watery grave of an impractical idea.

Once America’s most beautiful army base, this abandoned military fort on the coast of Monterey Bay has been left to the elements.

The only arched bridge made of stone on the entire Mississippi River.

One of the world's tallest, oldest, and most disgusting chocolate cascades.

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

This extravagant Art Nouveau rest stop features a million-dollar view of the Columbia River.

A massive sea stack famous for its appearance in The Goonies.

The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

From a neon Rapunzel to a bike traffic meter to a street fair color scheme, the most opened drawbridge in the US is a veritable art gallery.

The only road through the heart of Glacier National Park.

A bizarre house filled with an astounding array of collections.

A palatial art deco restroom.

A fence constructed completely of skis on Monroe Street.

What's that on the side of that building? Va Va Voom, it's Bettie!

Statue of Lenin, from Cold War era Czechoslovakia, now in a neighborhood of Seattle.

View the California coastline (and the home of Barbara Streisand) inch by inch with stunning, government-sanctioned aerial photography.

A man-made island in scenic San Francisco Bay.

An emerald-green grotto just a short trip from Austin.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

No Gordon Lightfoot song, only a barebones monument to greed.

Only known mainland rookery of the threatened Stellar sea lion.

The world's largest Holstein cow.

Haunting and beautiful trees, doomed to die.

America's most famous piece of self-built architecture.