One of the most extensive and well-preserved collections of dinosaur footprints in North America.

Red sandstone structures dominate this landscape, which has been inhabited for some 5,000 years.

The Grand Canyon’s original airport, which once welcomed pilots like Amelia Earhart and Charles Lindbergh, lies abandoned.

The ruins of a military outpost from the 1860s form the centerpiece of a Nevada state park.

Many believe these images represent interstellar lifeforms.

This former mining railroad is one of the best-preserved short lines in North America.

This location holds the truth to what truly happened that faithful night.

The man who voiced Bugs Bunny, Daffy Duck, Porky Pig, and more has a headstone reading, "That's all, folks!"

The oldest liquor store in the country is a model of resilience and mischief.

A star fort along the C&O Canal in western Maryland that protected America in three wars.

Three abandoned missile silos are hiding in plain sight behind a suburban development in Maryland.

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

Rusted and decayed, this former mining site is a portal to the past.

In the power of this waterfall, Alexander Hamilton saw the potential for industry.

One of the few remaining indigenous petroglyph sites in Nevada.

California's largest steel arch bridge.

The location where the iconic movie character declared it was time to go home.

The former home of the army detachment that captured Geronimo.

A glass display case holds the document that ended the Second World War—which one person signed on the wrong line.

An unexpected sinkhole in a desert flat within Gold Butte National Monument.

One of the largest collections of intact Victorian-era waterworks equipment in the world.

A unique collection of drawings that represent Fremont Native American culture.

The oldest pictographs on this decorated rock formation in California's Carrizo Plain date back as many as 4,000 years.

A planet-hunting astrograph built in the 1920s to seek out the so-called "Planet X" beyond Uranus.