The miraculous hydrant that saved the Mission District in 1906.

San Franciscans leave gifts and messages for the magical beings that live behind the tiny, mysterious door installed on a tree in Golden Gate Park.

This partially buried wreck is one of the most complete of its kind but is only revealed when the sea allows.

A collection of memorabilia from the Beat era in the back of a San Francisco bookstore.

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

A 300-ship graveyard, with a few still visible at low tide.

Visible below the waves are memorials to the city's Gold Rush dead.

A modern mechanical planetary system, part of a 10,000 year clock.

An essential stop before plundering, BYO Cutlass.

The one-time watch house for incoming ships at the Golden Gate now stands abandoned and hidden in trees.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

An artsy hidden staircase leads to breathtaking views of San Francisco.

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

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

In this century-old literary safehouse, print is alive and well.

A tiny theater hidden in an alley plays a constant stream of short silent films for anyone willing to peer through the peephole.

A nondescript building that's been functioning as a speakeasy for nearly a century and a half.

A shop full of natural curiosities, carnivorous plants, and costumed taxidermied mice.

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

Its buzzing collection honors vibrator history.

This shop specializes in oddities and Victorian-inspired wonders.

A winding path built in secret on the edge of the continent.

A 140-year-old castle with underground caves hidden in San Francisco.