An optical illusion found amid a logged redwood forest.

The liveliest ghost town in the state.

The most unique castle in all of Southern California, entirely constructed from repurposed materials.

A ruined hotel with an unlucky history and an eerie present.

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

Hidden above a drug store on a nondescript corner of Lincoln Heights is a private clubhouse for intrepid explorers.

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

A former utopian healing center created by a huckster and built by derelicts.

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

Julia Morgan's Moorish-Gothic labyrinth of fountains, trees, natural light and Oakland's notable dead.

These millipedes glow not out of attraction, but as a not-too-subtle warning.

The abandoned personal amusement park of the King of Pop.

The "Fun Spot of the Desert" is now a haunting ruin, and a reminder that putting a water park in a desert is a bad idea.

An extraordinarily ornate museum in San Diego holds wondrous anthropological treasures.

One of the ghostly stops along Route 66.

Nestled in the heart of San Francisco’s bustling Financial District stands a unique homage to the Mayan and Beaux Arts.

San Diego's most historic and haunted home.

A storybook European village in Berkeley.

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

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

In a city filled with Frank Gehry buildings, one stands out as one of the architect's weirder works.

The last of its kind in the country.

The remains of the first punk club in L.A.

Experience a quartz crystal sound bath inside a storied, all-wood sound-chamber.