This hollow steel globe is the second-largest in the world.

Long buried under the 20th-century landscape, this lift lock of the Alexandria Canal is the lone remnant of an ambitious early American transportation project.

The narrowest house in America is seven feet of pure spite.

A former major munitions plant that has been converted into a sprawling art space.

On the Oregon coast there is a natural hole that seems to be draining the sea.

Come for the speed, leave in love with the desert.

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

This gallery of prehistoric red ochre art lines the wall of a scenic segment in Utah's San Rafael Swell.

A cemetery full of touching tombstones from a community of railroad workers, uranium miners, and Cold War missile launchers.

The fifth-longest natural arch in the world, and the longest outside China.

Few things look more out of place than the electric blue ponds in the reddish-brown desert of Utah.

This monument marks the beginning journey of a wounded soldier's leg that ended up almost two states away.

The former home of the man whose radical ideas changed the nation.

This church is known as "The Home Church of George Washington and George Mason."

Considered by many to be one of the most dangerous highways in Alaska.

This monument is dedicated to those lost on June 6, 1944, in the town with that day’s highest per-capita casualty rate.

Washed out by the Johnstown Flood in 1889, the surviving portion of the original two-span bridge now resides at Fishing Creek.

France's national museum of scientific and industrial instruments.

Home to items never before seen by the public.

A monument in Washington D.C. marks the spot from which all other roads were supposed to stem.

The house where John Wilkes Booth conspired with his co-conspirators.

A museum dedicated to linguistics, from how babies learn to talk to endangered and extinct languages.

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

Housed in a century-old building, this museum's dedicated not just to soft drinks, but to the free enterprise system.