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.

Half of a house.

A hidden subterranean installation offers a view of the sky.

A whimsical antique shop with a strong air of mystery, filled with items from ages, and what feels like worlds, past.

An invitation-only museum of items natural and bizarre, arcane and exotic.

A playground built by the kids that is a child's wonderland, and a helicopter parent's nightmare.

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

The remains of a ruined mansion memorialize the 1906 earthquake.

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

A psychedelic labyrinth on the San Francisco bay.

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

Depicting scenes of everyday life - and specific individuals - in Great Depression era San Francisco.

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

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.

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

A huge musical instrument played by the ocean.

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.

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

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

9,000 square feet of vintage and modern mechanical toys, dioramas & sideshow curiosities.

Once the gateway to the utopian dream-village of a Civil War embalmer.

Social saloon from a scrapped trans-Pacific 19th century steamer.