Outsider art or homage to aliens?

A modest reminder of treacherous waters at the Golden Gate.

Gorgeous purple flowers drape from the world's largest blossoming plant.

Hand-crafted tributes to a stray cat named "Room 8" now cover this LA elementary school.

The world's most famous donkey lives in this pen.

Once the largest winery in the world, this castle-like building now sits abandoned on the San Pablo/San Francisco Bay shore.

Guarded by the Angel of Grief, the Stanford family tomb attracts an odd mix of halloween revelry and somber contemplation.

A lighthouse built to save lives that took quite a few with its treacherous location.

The oldest lighthouse on America's west coast no longer needs keepers, yet they maintain the site anyhow.

Concrete strongholds stand guard over the Golden Gate.

This mysterious petroglyph evokes the ancient swastika symbol but was later vandalized with the more troublesome Nazi one.

A rough granite monument marks the spot where Europeans first caught sight of the San Francisco Bay.

Recovered from the brink of extinction, at home in the Financial District.

Once close to extinction, there is no shortage of elephant seals on the beaches of Año Nuevo State Park.

The Empire Mine is "one of the oldest, largest, deepest, longest and richest gold mines in California."

This odd California folly seems like it was almost designed to accumulate urban legends.

One of few lasting examples of the brief octagon craze that developed into folly.

A brooding mansion of clinker brick stands out among the Victorian houses of Pacific Heights.

Barely visible foundations remain where Stow Lake’s “observatory” once welcomed visitors.

A comprehensive collection of Pez dispensers.

Celebrating the transformation of trash into objects of beauty.

Built by the inventor of the radio, this abandoned hotel has housed early radio employees, military men, and a dangerous cult.

Adolph Sutro's little-known, geographically inaccurate, deprecated monument.

Smooth basaltic rocks tell a tale of ancient glacial waterfalls.