This erect, phallic geological spire wasn't always named so domestically.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

Home to Hollywood history and a very special salt crystal.

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

Three hundred years of preserved Spanish colonial history in San Antonio.

A swamp and garden tour featuring local wildlife and exotic botanical specimens from around the world.

For 150 years one family has been producing the iconic hot sauce on a bayou island made of salt.

The walls of America's oldest masonry fort famously "swallowed" cannonballs.

One of the oldest, tallest, and most haunted lighthouses in America.

An 18th-century Spanish watchtower made entirely of seashell and concrete.

A historic lighthouse steeped in rumors of ghost and pirate stories.

An unnatural lake in a naturally beautiful setting.

Years of neglect and nature took a toll on this 19th-century lighthouse.

This beachside town is home to a diverse nature reserve, multiple cays, and one of the three bioluminescent bays in Puerto Rico.

This huge pile of volcanic boulders hides a stunning network of secret grottoes.

Rusting, graffiti-covered tanks litter the beach of this island, once used by the U.S. military for target practice.

On a clear day, you can see all the way to the Virgin Islands from the top of this observation tower built in the 1960s.

The hallowed ground of one of the worst atrocities in United States history.

The ruins of this abandoned fort now stand as a picturesque reminder of America's march West.

A multi-storied adobe complex has been inhabited for more than a thousand years.

A small metropolis of Pueblo cave dwellings have been carved right into the hillside of this national monument.

A phenomenal assembly of pueblos in New Mexico is the most complete example of ancient ruins north of the border.

The 7,000-year-old calcium carbonate formation creates a magnificent natural bridge.

An antique narrow gauge railway line still running through the Colorado and New Mexico mountains.