See massive fossils that are over 200 million years old in northeastern Arizona.

The only nuclear weapon assembly and disassembly plant in the U.S.

The first declared National Monument in the United States.

When ecosystems collide in the arid Southwest.

Victorian "Fancy Craft" Hair Wreaths and Relics.

Strange red rock formations that have been attributed to a higher power for hundreds of years.

While most of the games in this arcade take quarters, that would have been a small fortune when they were made.

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.

The final resting place of American icon Buffalo Bill, and a museum that aids in telling his tale.

A Civil War Museum with some notable medical antiques.

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

At 207 feet, one of the world's longest continuous escalators.

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

A traveling postal dog covered 48 states and more than 140,000 miles, and he lives on as taxidermy, patched up with a rabbit's foot and a pig's ear.

Home to items never before seen by the public.

Giant acorn-shaped 19th century gazebo from which suburban Washingtonians gazed upon the original "silver" spring.

Walk through the history of American pop culture.

Giant stone letters dedicated to the founder of Armenia's alphabet.