Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

Towering basalt columns, a creation of fire and ice.

Quite simply the largest tree in the world (by volume).

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

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

An old saloon in the West filled with history, and according to some, a few dozen ghosts.

A wild west cemetery in Tombstone, Arizona, provides a window into the Old West.

A classic Route 66 landmark that was built with scrap lumber and is held together with kitsch and puns.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

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

A museum dedicated to the alleged Roswell Incident.

Experience the hysteria of a 17th century witch hunt through goofy reenactments and wax dummies that should probably be burned at the stake.

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

Canyon walls shrouded in ferns.

A massive volcanic plug is now a protected area that hosts a number of bird species.

Limestone caves with spectacular showcase chambers.

A series of waterfalls and pools that flow through the 'Ohe'o Gulch and into the ocean.

Take shelter from Hawai'i's tropical heat under the massive canopy of largest Banyan tree on the island.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.