You can walk through the first Boeing Air Force One, which famously carried JFK's casket from Dallas back to D.C.

In one of America’s oldest mountain ranges, a long-awaited section of a scenic highway is now open to the public.

The Battle of Atlanta in 360 degrees, featuring a corpse that bears a striking resemblance to Clark Gable.

An atomic bomb-proof strongbox protects the U.S. Constitution from terrorists and thieves.

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

A recreation of the doomed ocean liner in the middle of the Smoky Mountains.

A bit of retro transportation flair preserved in the world's largest department store.

The world's longest known cave system.

This unique crypt designed by Frank Lloyd Wright for his longtime friend was not completed in either man's lifetime.

One of Frank Lloyd Wright's greatest—and favorite—architectural masterpieces was almost lost.

Ruins of a once-prized railroad station in New York.

An abandoned town is hidden in Great Smoky Mountains National Park.

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

This replica of the Greek structure is in the heart of Nashville.

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

This restaurant proudly displays bread signed by the 39th president.

An unusual, super-sized grocery adventure awaits in an Ohio suburb.

A small town museum celebrates the history of the Ohio county that produced Annie Oakley and other famous figures.

An unassuming 13-acre park is home to over 12,000 roses.

These sub-farmland caves are home to a majestic stalactite known as the "Crystal King."

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

A hamlet full of permanent Christmas spirit holds one of the earliest theme parks in the United States.

Dozens of houses in the Adirondack Mountains are reminders of a literal "cottage industry" to cure people of a deadly disease.

A theme park featuring a replica of Noah's Ark built to the measurements specified in the Bible.