This once-booming Gold Rush town is now home to a herd of feral donkeys.

This 29-ton granite ball spins around at the slightest touch thanks to a scientific phenomenon.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

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

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

An early-19th-century hotel with a past that is steeped in the Civil War.

A hotel with a rich Wild West history of miners and bootleggers.

The Corinthian columns that towered over Abraham Lincoln’s inauguration stand proud.

This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

This black shoreline is made up of exploded lava particles.

A state park that once served as an important river crossing, and now offers protected lands for endangered plants and animals.

The 72-foot giant escaped confinement in a large patch of mulch only to be reburied in the sandy shores of the Potomac River.

Baltimore's classic clock tower was once topped by a rotating, 20-ton medicine bottle.

This beautiful stone arch bridge wasn't even expected to stand for one day, but people have been crossing it for centuries.

This scenic Maryland park was the site of one of the worst prison camps of the Civil War.

The longest escalator in the Western Hemisphere takes over three minutes to ride down.

Captain John Smith thought these cliffs were amazing in 1608 but sharks thought so 20 million years before him.

Despite violent work crews and massive delays this abandoned canal tunnel was built to last into the modern day.

The remnants of a wooden-hulled fleet built and abandoned in WWI, now home to a thriving ecosystem.

The land is home to swimming ponies and a legendary 18th-century treasure.

An abandoned quicksilver mining town surrounded by the Big Bend parks.

An idyllic swimming pool tells the tale of Hemingway's trouble with women.

The highway's southernmost spot is a beloved local attraction.

The third tallest lighthouse in America once guided author Stephen Crane to safety.