A working cattle ranch with remarkably well-preserved prehistoric petroglyphs and ancient ruins.

Thousands of Mexican Free-Tailed Bats soar around an abandoned storm drain at sunset each summer.

Limestone caves with spectacular showcase chambers.

America's only nuclear missile silo open to the public.

Ancestral Puebloan ruins, natural arches, and box canyons abound in this seldom-visited corner of Monument Valley Navajo Tribal Park.

A stealthy Apache hideaway that became the haunting site of a mass grave.

Rippling sand dunes frozen in the Arizona rock.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

The installation’s official name, “You Who Are Getting Obliterated in the Dancing Swarm of Fireflies,” says it all.

A volcanic tunnel illuminated by natural skylights offers a shaded respite from the desert sun.

Named after a bandit and the star of several Hollywood prehistoric landscapes, these sandstone formations are a historical part of the Los Angeles natural landscape.

The final resting place of a space program monolith.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

The now-abandoned tunnels were built for the transcontinental railroad on the route where the first wagon train entered California.

Trails through lava-carved tube-caves display sparkling bacteria and a rich history.

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

Eons old volcanic activity created one of the most stunning rock formations in the United States.

San Francisco's newly reopened hands-on science museum.

Carved by a waterfall in a hard-to-reach rock formation, this heart-shaped rock has inspired romantics for decades.

Panorama exhibition hall in old silent theater with a beautiful backyard garden.

A winding path built in secret on the edge of the continent.

Scores of vintage street lamps shine along L.A.’s Miracle Mile.

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

A one-of-a-kind collection of a unique medium.