The engineering wonder and pleasure dome of a much-maligned emperor still holds undiscovered secrets.

2300-year-old Roman road connecting the empire.

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

Rome’s legendary peephole vista is also a former Crusader stronghold.

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

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Medicinal spa created from the mineral-rich runoff of a geothermal power plant

One of the world’s largest collections of petroglyphs records 2,000 years of human activity.

Bizarre lunar-like landscape with thousands of large stone "hoodoos."

This set of three large, volcanic hot springs is a favorite haunt for intrepid divers.

One man has installed bathtubs into the Utah desert floor to harness the powers of a natural hot spring.

Most-visited and most-photographed slot canyon in the American Southwest.

A sharp bend in a dramatic river canyon cut through red rocks.

The Grand Canyon of Texas.

Thirteen pastel palaces in downtown Charleston add a gorgeous splash of color to the city.

A stack of stones steeped in Irish folklore, much like the hero they're connected to, hide in plain sight.

Charleston's historic city jail once held everyone from pirates to Civil War POWs.

South Carolina's last remaining slavery auction house is now a museum devoted to its own tragic history.

This high point in the Great Smoky Mountains is said to be home to the chief of all bears.

A Rocky Mountain city provides a happy ending for a pinto pony and his Brobdingnagian red chair.

This unassuming cheese empire in rural Oregon churns out more than 150,000 pounds of cheese each day.

This gorgeous beach hides behind two headlands in Oregon's Ecola State Park.

A 90-foot-tall psychedelic "tree" on the side of the highway has baffled passersby for decades.

An ill-fated attempt to grow wheat in the sagebrush steppe of northeastern Nevada.