San Francisco's oldest surviving monument and meeting place for 1906 survivors.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

The smallest country in the world.

This Old West eatery along America's Loneliest Road was originally a stop on the Pony Express.

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

This rest area is also home to a remarkable petroglyph site.

Where a guard killed nine German prisoners during one of the worst 20th-century POW camp massacres in U.S. history.

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

Oddly shaped rock formation, misassociated with a nearby utopian community.

A dangerous narrow-gauge railroad once traced a route through this striking canyon.

This razorback ridgeline has doubled as a scenic drive since the early 1900s.

Giant works of art interspersed throughout meadows and woodlands offer a new discovery at every turn.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

This rare triple-jurisdiction drawbridge passes through Virginia, Maryland, and Washington, D.C.

The world's largest dead polar bear, immortalized by taxidermy and Hunter S. Thompson.

The only bridge in the United States where BASE jumping is legal without a permit year-round.

These falls, sometimes called the "Niagara of the West," still put on a good show at the right time of year.

Home to the deepest rift anywhere on Earth.

Supposedly Satanic numbers adorn this preserved submarine sail.

This museum glorifies the humble potato.

A museum dedicated to the history and art of staying clean.

Dig for your own trilobites in this goldmine of invertebrates.

Behind these delicious arepas lies a true New York success story.