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

Gold Rush ship-turned-hotel buried underneath San Francisco's financial district.

Fonts are born and bred here at the oldest letterpress type foundry in the United States.

The remains of a 12th-century chapter house in Golden Gate Park.

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

The stones that traveled from Spain to eventually become a holy place for San Francisco's nature worshippers.

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

Golden Gate Park's historic collection of plants.

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 turn of the century masterpiece has a mysterious goaty interloper.

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

The randomness of this wall of lava lamps helps encrypt up to 10 percent of the internet.

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

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

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

Staircase winds down the side of Telegraph Hill through gardens, wild parrots flying overhead.

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

Olfactory delights in San Francisco's Botanical Gardens.

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

Carnivorous plants, medieval aphrodisiacs, and the largest original wood structure glass conservatory in the western hemisphere.

Get lost in this haunting fairytale art walk through a man-made eucalyptus grove.

There is no trying to fall in love with this Star Wars fountain, you just do or do not.

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

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.