The photos landed on r/sanfrancisco and collected the usual current of response: people tagging corners they recognized, someone zooming into a storefront to identify a sign, someone else flagging the framing on a particular shot as genuinely well-composed. The walk itself — that particular diagonal, north to south, higher ground to higher ground with the flatlands in between — threads through more distinct micro-climates of the city than almost any other you could plot on a map without a car. Dragon gate at one end, the summit of Bernal and its off-leash hill at the other, and in between: the produce vendors on Stockton, the Vietnamese sandwich shops on Larkin, the long residential blocks of the Mission where the same taquerias have been next to the same laundromats for decades, the small parks that accumulate different crowds at different hours.

No single image from the set circulated wider than the others. What people seemed to respond to was the accumulation — the evidence of someone moving through the city at walking speed, which is still the pace at which you notice that the awning on a bakery has changed color, or that a vacant lot now has a chain-link fence with a permit notice zip-tied to it, or that somebody has placed a single folding chair on a stoop in a patch of afternoon sun and it looks, for a moment, exactly right.

Tomorrow, walking any stretch of that route, you'd see what the photographer saw: the same blocks, the same light if the fog cooperates, the same accumulation of detail that only resolves into a picture once someone stops moving long enough to frame it.