In a 345-million-year-old cave that's 200 feet underground, dinner awaits.

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

Most-visited and most-photographed slot canyon in the American Southwest.

This gorgeous stretch of coastline is home to beautiful views and centuries-old rock art.

A favorite haunt of dinosaur loving children and hallucinogen loving hippies alike.

Crypt mausoleum in cathedral's basement contains relics of third century Roman martyr, Saint Vibiana.

A hospital closed seemingly in the middle of operations, leaving behind fodder for horror films and ghost hunters.

The most isolated mailbox in America lets desert travelers record their passing.

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

One of the largest trees of its kind in California.

Not truly a ship nor a building, the Navy's first and last "landship" is now abandoned due to clerical issues.

This futuristic bridge is one of the longest self-anchored pedestrian bridges in the world.

North America's largest accredited model railroad museum.

This little blue house pokes out over the campus of UC San Diego, seven stories high.

An inconspicuous footbridge beloved by San Diego locals.

During prohibition, corrupt city officials ran drinking dens under the streets of Downtown Los Angeles.