Once America's tallest structure, now a Baltimore landmark.

This titanic oil company sign is a reminder of the Americana boom of the 1970s and also its commoditization.

The highest paved road in North America winds its way up Mount Blue Sky in Colorado to an altitude of 14,130 feet above sea level.

This statue of an obscure comic strip hero stands as a tribute to patriotic service and a cautionary tale about embracing fads.

Race through the maze, get your name on the sign.

The only royal palace on U.S. soil has been a territorial capitol, a military headquarters, and a prison for a queen.

America's Most Wanted's set resides in this tribute to the history of crime and punishment.

Famous church recognized for both its unique design and disciplined monks that live according to the Benedictine discipline.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

One of the most scenic stretches of road in America winds between some of the country's oldest trees.

This famous bridge twisted itself into oblivion, but not for the reason you might think.

A wall of chewing gum moonlights as collective art.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

Quite simply the largest tree in the world (by volume).

Bits and pieces from the ill-fated Donner Party's winter cabins.

This Nevada lake holds its titular natural pyramid and, if the legends are true, a number of dangerous spirits.

Only intact Ichthyosaur skeleton in the United States.

Singing sand that stands as the final remains of an ancient lake.

The first U.S. town to secede from the Union, only to vote themselves right back in.

Officially named the "Loneliest Road in America," this barren stretch of Nevada road offers almost nothing but sky and open fields.

These once-beautiful historic graveyards are set against the barren Virginia City hills.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

400 million-year old limestone caverns nestled in the Ozarks served as shelter and a hideout for cultures throughout North American history.