Architectural monsters are devouring this palace's every door and window.

2300-year-old Roman road connecting the empire.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

A breathtaking bridge that crosses a vast gorge over a river's torrents, and has a tale of a devil architect attached.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

A nearly 500-year-old sculpture depicts a man eating a sack of babies, and no one is sure why.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

The only natural lake in the world that drains into both the Atlantic and Pacific Oceans.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

An architect's childhood fantasy treehouse made real.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A beautiful geyser under environmental threat.

The wreckage of a World War II bomber is hidden high in the Colorado wilderness.

Each year, teams of the world's best snow sculptors have 65 hours to create frozen masterpieces.

A recreation of an Old West apothecary full of curios.

A small horde of mythical creatures lurk almost imperceptibly within the museum's wildlife dioramas.

The world's largest key collection features keys to the White House, Frankenstein's castle, and Hitler's bunker.

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.

The largest source of fossilized insects anywhere.

Despite being one of the most photographed vistas in the Rockies these twin peaks are rightfully known as the "Deadly Bells."

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

When ecosystems collide in the arid Southwest.

Paranormal experiences in this hotel's room 217 led Stephen King to write "The Shining."