We found that people tended to conceptualize San Francisco in terms of “main drags” and “mini cities” – commercial corridors that attract people – contrasted with “mini suburbs” – primarily residential centers that are often perceived by people who don't live in those neighborhoods as “boring” places where “there's nothing really there.” The balance between vibrant and inviting corridors and seemingly monotonous residential areas results in some areas of the city being described as more exciting than others.

"I think of San Francisco as being a bunch of main streets in small towns, all smushed next to each other."

San Francisco’s Deadzones and Corridors is a map depicting both where the city’s “corridors” or main drags are, the neighborhood names associated with them and a measure of “neighborhood-ness” throughout the city (the residential density metric). The map has three layers: a choropleth (heatmap) of residential density in red tones, areas zoned for commercial activity in blue and street segments with verified commercial activity in yellow.

The distribution of lower residential densities in the Richmond, Sunset and Parkside (rows of single family homes), higher densities in the Mission and Tenderloin (more apartments), and isolated areas of high densities in the South of Market region (high-rise condominiums) makes intuitive sense. Zoning data comes from the San Francisco Planning department, but does not necessarily translate into actual commercial development. The verified commercial strips were ground-truthed on Google Maps, Yelp and Walkscore.com.

"The Outer Sunset and Outer Richmond are sort of drive through areas for me. it's the equivalent of flyover country."

The resulting map depicts a lot of the sentiments that were expressed in the interviews. The majority of neighborhoods in the city each have a single street that commercial activity is centered around (save for the Mission which has Misison Street, Valencia Street and 24th Street). Not only does the southern half of the city have a low residential density throughout, its commercial corridors are shorter, fewer in number and are distributed further apart.

San Francisco's Deadzones and Corridors