Bison, America's national mammal, are staging a slow comeback in Ohio's prairie parkland.

At the center of this cemetery stands a 2,000-year-old burial mound of the Adena culture.

An abandoned, rusty old relic of railroad history stands at attention over the Cuyahoga River.

This Czar-funded, onion-domed, lavishly muraled Orthodox Church played a starring role in "The Deer Hunter."

A slab of sandstone covered with mysterious 1,000-year-old rock carvings from a vanished North American culture.

A throwback train ride transports passengers through one of the lesser-known national parks in the country.

Funded by John D. Rockefeller, this is one of the earliest, and most beautiful, shopping arcades in America.

The only remnant of a small mining town is an abandoned railroad tunnel that is steeped in ghostly lore.

The world's largest mineral hot springs is home to a herd of bison, a free public bath house, beautiful mineral formations, and a terrifying swinging bridge.

At the time of its completion, it was the tallest dam in the world.

Around half a million years ago, these magnificent columnar basalt cliffs were formed from cooling lava.

Devilish landscape, once cinema home to giant alien bugs, now derelict roadside attraction.

The world-record holder for the longest bridge stretching continuously over water.

The heroic sled dog of the 1925 serum run is preserved in taxidermy.

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

One of the world’s largest and deepest freshwater springs, where mastodons once roamed.

A world-class observatory in the California desert.

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

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

This massive roadside mascot was the first version of the giant to illustrate his butt.

The only road through the heart of Glacier National Park.

Eight rare Corvettes are swallowed up by a sinkhole in Kentucky's National Corvette Museum.

The world's largest rotating world.

This haunting tombstone comes complete with a heartbreaking story of love and loss.