A mass grave for victims of an airline disaster that led to much-needed safety improvements for commercial flights.

The eroded core of an ancient volcano is now accessible by a short hike.

A nature and cultural preserve named for its multitude of petroglyphs carved by the Northern Sinagua people.

This Arizona observatory is famous for investigations into Martian life, and as the place humans first spotted Pluto.

This grassy, tree-lined hill shares a name with the much-loved novel that it inspired.

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

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

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

Hundreds of handmade critters fill this tiny window gallery in the heart of Portland's Alberta Arts District.

An Aztec temple, the largest man-made pyramid in the world, sits buried in earth with a Spanish church set on top.

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

A giant Troll lurks under one of Seattle's oldest bridges.

Make your reservation to have coffee with some kitties.

The flock of plastic poultry is an ode to the classic comedy staple.

This opulent Pueblo Deco movie palace melds Art Deco and Native American motifs.

The "Bridge Over the Atlantic" lets you cross the waterway in mere seconds.

Hanging within this medieval church are the bones of a beast allegedly slain by a fourth-century saint.

The influential philosopher's old residence is commemorated in a small English town.

This enchanting mountain plateau celebrates spooky local folklore.

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

The yawning maw of this pagan visage is said to bite off the hands of liars.

The underground sanctuary of a mysterious ancient cult.

This ancient Roman arch misled treasure hunters for centuries.