Every fall this lake mysteriously drains, like a bathtub with the plug pulled out.

Guns that have been defending San Francisco since 1904.

Beneath the southern end of the Golden Gate Bridge is the “Gibraltar of the West Coast,” a fort built to protect the San Francisco Bay from naval attack.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

The second building of its name to occupy this location might be the finest flatiron building in San Francisco.

Chevron maintains one “Standard” brand station per state so it doesn’t lose the trademark.

This giant head is all that remains of a once proud statue that survived an earthquake but not a fall off of a wagon.

This contorting sculpture is the tallest in San Francisco.

A pair of mutilated bronze octopuses slump at the base of the monument honoring California's admission to the U.S.

This tall and trim architectural oddity is one of the skinniest buildings in San Francisco.

These six walrus head statues harken back to a time when this area wasn't far from the oceanfront.

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

Prone to disastrous fires, the city of San Francisco has the Guardian, a fireboat gifted by residents, to watch over them from the bay.

Big gun installations, built over a massive cemetery, now abandoned & hidden in trees.

A hidden gem, named after a San Franciscan icon, offers spectacular views of the Pacific Ocean.

The sole surviving relic of the San Francisco neighborhood cobbled together from old horsecars and streetcars.

Forgotten and then destroyed by fire, this was once one of the largest saltwater swimming pools in the world.

This grinning pup statue is all that's left of what was once a ubiquitous Bay Area diner chain.

This massive redwood tree has stood in Northern California for nearly 2,000 years.

Elephant seals and sea lions have turned the abandoned buildings on this island into their endangered love shack.

A New England-style lighthouse along California's beautiful Highway 1 gets a re-do.

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

Eat a tasty meal in the house where John Steinbeck was born.

It should come as no surprise that the world's largest artichoke lies in the town that calls itself the "Artichoke Center of the World."