Almost every list of the best things to do in San Francisco describes the same eight-mile loop: a bridge, a pier, a prison island, a crooked street. That loop is fine and it is also a tiny fraction of what is here. The genuinely strange stuff in this city is scattered across residential neighbourhoods, costs nothing, and requires only that you be willing to take a bus somewhere that is not on a postcard.
Most of these are unmarked and depend on tide, weather or time of day. Ask Karpo what odd things are worth doing near you right now.
The one that plays the tide
At the end of a jetty in the Marina sits a sound sculpture built from reclaimed granite and a set of pipes that run down into the bay. As the swell moves, air and water push through the pipes and the whole structure gurgles, booms and whooshes. It was built in the mid-1980s by an artist and a stonemason working with the city's exploratory science museum, and the material is salvaged from a demolished cemetery, which gives the stonework its oddly funereal carved fragments.
The critical detail is that it only works at high tide. At low tide it is a pleasant walk to a pile of rocks. Check a tide table, go within an hour either side of the high, and put your ear against the pipe openings rather than standing back politely — the sound is quiet and physical rather than loud and obvious.
The slides in a residential garden
Halfway up a steep block near the Castro there is a small park with two long concrete slides running down the hillside. They date from the 1970s, were reportedly designed with input from a local teenager, and are used mostly by adults who bring a flattened cardboard box to go faster. There is usually a supply of cardboard stashed at the top by whoever came before you, and the etiquette is to leave it there when you finish.

It is free, it takes fifteen minutes, and it is in the middle of a residential street, which means the one genuine rule is to keep the noise down. It is also considerably faster than it looks, and the landing at the bottom is concrete.
The Victorian optical device by the ocean
Behind the site of the old cliff house, perched above the sea, is a camera obscura — a darkened room with a rotating lens and mirror on the roof that projects a live, moving image of the coastline onto a concave dish inside. The current structure dates from the late 1940s and is one of very few working examples left in the country. Waves, seals and passers-by appear on the dish in real time, in colour, in a resolution that photographs cannot reproduce.
It costs a few dollars, takes ten minutes, and is the single strangest small thing on this list. It is also weather-dependent in the opposite direction to everything else: a bright day gives the best projection, so this is the one to save for the clear afternoon.
The bookshop, the mural alleys and the stairways
Three more categories that reward wandering. The city's stairway network — hundreds of public staircases connecting streets that a car cannot navigate — includes several with elaborate mosaic risers and views that no vantage point on the tourist loop can match. The mural alleys in the Mission are open-air galleries that change constantly and are best seen on a weekday morning when the light is on them.
And the independent bookshops here, several of which have been operating since the 1950s and one of which was a defendant in a landmark obscenity trial, are functioning cultural institutions rather than retail. Going in and reading in a corner for an hour is expected behaviour.
Where the odd things cluster
There is a rough geography to this. The Marina and the Presidio hold the coastal oddities — the sound sculpture, a set of decommissioned artillery batteries you can walk into, a wave-battered beach reached by an unmarked trail. The Castro and Noe Valley hold the residential ones: slides, stairways, unexpected gardens. The Mission holds the human-made ones — murals, small museums, a nineteenth-century mission church that is the oldest surviving structure in the city.
The Outer Richmond and the west side hold the strangest: a ruined bath house complex on the rocks, a labyrinth cut into a headland, a windmill in the corner of the park. That whole stretch of coast is walkable in an afternoon and contains more genuine oddity per mile than anywhere else in San Francisco.
Stringing them together
The mistake is treating these as individual destinations. Each is fifteen to thirty minutes long, which makes any of them a bad reason to cross the city on its own. Grouped by neighbourhood, they become a good half day: the sound sculpture, the artillery batteries and a beach in one loop; the ruins, the labyrinth, the camera obscura and the windmill in another; the slides, the stairways and the mission in a third.
Pick the loop by weather. Clear day, go west for the coast. Grey day, do the Mission, where the murals look better under flat light and there is somewhere warm every fifty metres. That single decision is most of the planning, and everything on all three loops is either free or costs less than a coffee.
Tags: #SanFrancisco #OffbeatSF #HiddenGems #WaveOrgan #SewardSlides #CameraObscura #ThingsToDoSF #SFSecrets #Presidio #MissionDistrict #OuterRichmond #BayArea #FreeSF
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Ask Karpo first
Ask Karpo which odd corners of San Francisco are near you right now, whether the tide or the weather matters, and what else is on the same loop.



