These subterranean storage areas hold emergency water reserves.

A shining, cold, black organ lies in San Francisco's financial district.

A monumental cross hides in the trees in Golden Gate Park.

Once the largest windmill outside of Holland, with enormous 114 foot sails.

An enormous illuminated figure dances on the Las Vegas strip.

An elaborate gift from Claus Spreckels is now a piece of San Francisco history.

The key to turning shifting dunes into the green oasis of Golden Gate Park.

Faceless white figures loom over the city from the rooftop.

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

A man-made island in scenic San Francisco Bay.

Since 1973, this block has been home to the most concentrated collection of murals in San Francisco.

A library built during San Francisco's pioneer times is a student's retreat, bibliophile's sanctuary, and chess player's delight.

The miraculous hydrant that saved the Mission District in 1906.

The giant pair of sexy legs sticking out the window of this costume store have become its main draw.

Golden Gate Park's historic collection of plants.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

This private residence was the template for one of the most beloved television homes of all time.

This shop and studio is dedicated to the art of the book, from letterpress to bookbinding.

San Francisco's oldest surviving monument and meeting place for 1906 survivors.

A hidden subterranean installation offers a view of the sky.

The oldest burial ground in the city, final resting place of city founders, Ohlone natives and murderers alike.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.