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

An abandoned 1920s-era stretch of cabins now overshadowed by the 66 Motel.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

World's largest collection of serial killer artwork and other macabre exhibits.

A psychedelic labyrinth on the San Francisco bay.

A huge musical instrument played by the ocean.

More than 25 fully functional scale replicas of famous lighthouses dot the shores of Lake Havasu.

This immigrant bridge once spanned the Thames but is now a fixture of an Arizona city.

This conservation area is also home to many of the region's desert tortoises.

While exploring the desert, you can stop by the home of a fictional heretic from a parallel universe.

Explore 10 acres of environmental sculptures.

Located on 420 acres in the high desert, this spiritual center is dedicated to the "science of the future."

This park is home to California's first oil boomtown, with structures that have stood for more than a century.

The remnants of a failed socialist commune can still be found just off a California highway.

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

One of the world's oldest and most massive living organisms is a grove of quaking aspens.

A ghost town at the airport is now a refuge for blue butterflies.

Formerly Fire Station No. 27, the museum is a hidden gem in the heart of Hollywood.

A historic fort commemorating the United States' naval history.

This quirky UFO-shaped curiosity is often mistaken for the airport’s control tower.

Remants of foundations, streets, and streetcar tracks inhabit the cliffs where a landslide occurred in 1929.

A long-vacant Scottish Rite temple in Hollywood has been converted into an art museum filled with Masonic relics.

This grand memorial remembers the 20 members of the Los Angeles Times killed when the office was bombed.

Opened as part of the New Deal, the training facility now features World War II-era structures and a pylon that once stood at the World Trade Center.