The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

An abandoned mine where dreams of quicksilver trickled away over 75 years ago.

The wood bears a hidden love note carved by a young Johnny Cash.

Two small markers remember the Alamo's feline protectors.

An ivy-covered arch bridge dedicated to Tejano music singer and legend Rosita Fernandez.

Of course the grave of JFK's assassin is surrounded by conspiracy theories.

The highest point in Texas is capped by a big silver pyramid.

Natural catch-basin rocks covered in thousands of drawings spanning many millennia.

Steep canyon walls hide a forested oasis in the West Texas desert.

The summer home of the largest colony of bats in the world.

Housed in a century-old building, this museum's dedicated not just to soft drinks, but to the free enterprise system.

Visitors can walk over the largest concentration of Columbian mammoths to have died from one event.

A Texas cave network is home to some of the world's most spectacular-looking and bizarrely named mineral formations.

The Grand Canyon of Texas.

This mansion turned restaurant was once a pitstop for Al Capone during his travels.

An engraved boulder marks the spot where Patsy Cline's life ended in a plane crash.

In one of America’s oldest mountain ranges, a long-awaited section of a scenic highway is now open to the public.

These early tent-shaped grave coverings are unique to Appalachia.

Hiding behind a grocery store is a spectacular cavern carved as part of an old limestone quarry.

This large cave is a summer home to thousands of bats and has a rich history dating back to prehistoric times.

Labor provided by Great Depression-era programs restored these 25,000 acres in Tennessee.

Mile-long cave system near Great Smoky Mountains.

More than five miles of underground passageways.

Visit this playground of waterfalls, caves and sinkholes.