As the freeway erodes the gridded urban fabric, the discrete space of the conventional urban street begins to disappear. The newly imploded space is bridged over and tunneled under in a successive overlay of centripetal figures.

These alternate pedestrian routes -- interblock spines -- reroute the activity of the grid into new connections provided above and below street level, driving the remaining pedestrian activity into an interior world of skybridges, atriums, and tunnels. Elevated or subterranean pedestrian passages directly link freeways and garages to vast corporate interiors, consolidating them all into an autonomous centripetal network.