On the Oregon coast there is a natural hole that seems to be draining the sea.

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

"Only the devil could play golf here."

Rippling sand dunes frozen in the Arizona rock.

One of the most unusual geological features, recognizable from a dozen hit movies.

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

Oregon's unexpected high desert, displaying layers of time in a colorful show.

Towering basalt columns, a creation of fire and ice.

A part of the world's largest marsh seems to be growing bright red Martian grass.

Seemingly grown on some other world, these New Mexico rock formations look like a disused science fiction set.

Intensely colorful calcite pools in Southern China.

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

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

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

The drama of nature in full effect in this Nevada State Park.

A tiny microvalley etched into the side of Knocknarea Mountain hides another world.

Sandstone rock formations that look like they belong on the cover of a progressive rock album.

Smooth basaltic rocks tell a tale of ancient glacial waterfalls.

An arsenic-filled pool in the Grand Canyon takes on the appearance of a giant, overflowing pumpkin.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.