The goal this exercise was to establish physical interdependent relationships among San Francisco's branch libraries in order to define a central location for accessing the whole of the library system's collections | the nexus of the city's information network.Created in the absence of the elevated roadway north of the Fell Street exit ramp, a residual void within the city fabric meanders through the Western Addition neighborhood. By mapping the x-y-z coordinates ( address & elevation ) of the city's branch libraries on a terrain model, derived from a USGS topographical survey map, it was possible to determine each library's three dimensional proximity to the site. Synaptic connections were created between each of scattered locations and projected across the site which resulted in a dense matrix of of narrow horizontal planes suggesting structure and enclosure.