This Stonehenge-inspired solar calendar stands alongside a landfill, in the middle of the Nevada desert.

A dangerous narrow-gauge railroad once traced a route through this striking canyon.

An eclectic collection of artifacts from the Wild West is preserved in a remote fictional pioneer town.

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

Harder layers in colorful sandstone weather out as prominent “fins" and even more intricate and bizarre shapes.

Colorado's only true geyser is hidden within the San Juan National Forest.

An unexpected sinkhole in a desert flat within Gold Butte National Monument.

Many believe these images represent interstellar lifeforms.

One of the few remaining indigenous petroglyph sites in Nevada.

The Grand Canyon’s original airport, which once welcomed pilots like Amelia Earhart and Charles Lindbergh, lies abandoned.

More than a century old, this trading post resides in the Navajo Nation.

This massive geographical sculpture is so subtle, it's possible to pass by it without noticing.

Ute tour guides have been sharing the ancient dwellings and rock art inside this large park with visitors for more than 40 years.

This Native American settlement dates back to the Pueblo II period.

This small interfaith chapel lies not far from the rim of the Grand Canyon.

Michael Heizer's masterwork in the Nevada Basin.

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

Despite the name, it's unclear if this small depression in northern Nye County was actually caused by falling space debris.

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

One of the most extensive and well-preserved collections of dinosaur footprints in North America.

A whimsical roadside community of little metal people.

A breathtaking array of ancient Pueblo structures and artifacts counterintuitively preserved by neglect.

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

The site where a nuclear bomb was lowered over 8,000 feet underground and detonated as an experiment in natural gas extraction.