A monument to the one-armed geologist who led the first documented expeditions through the Grand Canyon.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

The largest wildlife crossing in Utah allows local fauna to safely traverse the six-lane Interstate 80 at Parleys Canyon.

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

The fifth-longest natural arch in the world, and the longest outside China.

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

Experience a charming 1930's version of "infotainment."

A Norwegian-born sculptor created these soaring guardian angels at the entrance to Hoover Dam.

The arch that celebrated the completion of the Lincoln and Victory highways.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

An architect's childhood fantasy treehouse made real.

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.

A beautiful geyser under environmental threat.

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

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

The interior of the Overlook Hotel in "The Shining" was based on this Yosemite original.

A glimpse into the lives of the the Miwok and Paiute people in Yosemite National Park.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

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

This raised bulls-eye visible from space was the subject of an intense geologic controversy.

A house carved into a rock in the 1940s.

One of the most scenic stretches of road in America winds between some of the country's oldest trees.

Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.