A serpentine highway twists and turns over the treacherous Norwegian Sea.

An underground city beneath Krakow's postwar socialist utopia.

Veryovkina Cave is more than 1.3 miles deep—the deepest known in the world.

An abandoned hotel in the highlands of Bali is shrouded in stories of ghosts, curses, and corruption.

6000-year-old coal fire moves one meter per year.

This mesmerizing and surreal landscape features intricate patterns of white and red sandstone.

This stunning mass of ice spans 121 square miles and is still growing.

This stately monument has been wearing a traffic cone hat for decades much to the delight of the locals.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

This underground cave located in the most barren reaches of Idaho is filled with ice year-round.

The complex has been abandoned since the Croatian War of Independence, barring a stint as a set for 'Game of Thrones.'

A natural gas leak provides a flickering flame beneath a waterfall.

A South African bar inside a hollowed out 6,000-year-old Baobab.

The chefs at El Diablo use heat generated by an active volcano to cook the food.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

Once the "Eighth Wonder of the World," this iron railroad bridge was decimated by a tornado.

The first declared National Monument in the United States.

Tour the world's largest deep-hole dimension granite quarry, where you can view the plant where gravestones are made and roll a ball down the outdoor granite bowling alley.

These towering cliffs jut dramatically from the middle of a barren desert.

The second-longest continuous wall on the planet protects a hidden secret in the deserts of India.

This small 16th-century church in Athens is almost entirely surrounded by a modern building.

The platform atop this verdant volcano was built with the help of a royal elephant.

Starting with nothing more than discarded conch shells, one man has built an island/bar that would make Jimmy Buffet jealous.

270 million year-old forest of stone.