This museum showcases the history and contributions of the U.S. Army to the medical industry, both on the battlefield and off.

A National Historic Landmark with a scenic clock tower and park filled with deer and peacocks, plus a military museum.

Colorful curls of hand-blown glass form a captivating tower in San Antonio's Central Library.

Modern technology and live displays tell the story of the Pacific during WWII for the Internet generation.

An enormous pink granite batholith, long attributed with spiritual powers by the Tonkawa Indians.

An immense cave that has served as an outlaw's treasure trove, an underground dance hall, a nuclear fallout shelter, and much more.

This grimly-titled Texas cemetery is all that remains of a Wild West settlement with possibly the worst name.

The world's longest known cave system.

You can walk through the first Boeing Air Force One, which famously carried JFK's casket from Dallas back to D.C.

Inside houses a vast collection of military aircraft and missiles spanning the ages.

Crystal hunters can dig for their own stones at this DIY mine in Arkansas’ quartz belt.

A city park that sits on top of a freeway.

This downtown Dallas art installation is always on the lookout.

Once the smallest park in the national system.

The largest cattle market on earth holds live auctions open to the public every week.

The Bucyrus-Erie model 1850B electric shovel, or "Big Brutus," the largest existing electric shovel in the world.

The first declared National Monument in the United States.

One of America's first dinosaur parks gives a window into Depression-era paleontology.

One of the first intercontinental ballistic missile sites in the United States.

The granddaddy of all tourist traps, built on ice water, jackalopes, and a giant dinosaur.

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

The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

Legends surround this jagged rock formation in the New Mexico desert.

A wacky, UFO-shaped house in a suburban neighborhood.