400M Through Street Network

In many cities around the world, there is a surprisingly consistent pattern of through vehicular str

At a larger urban scale, there is need for higher-speed vehicular mobility. But at a smaller sub-neighborhood scale, there is a need for resident-pedestrians to have their own sanctuary, free of the dangers and disruptions of areas dominated by vehicles.

Therefore:

When laying out street grids, use a rough spacing of 400m (¼ mile) or less for principal through streets. Within these roughly 400m areas or “sanctuaries,” make shorter, interrupted, lane-like streets that accommodate vehicles, but allow pedestrians to dominate.

When … Within a Polycentric Region (p. 24), we need to establish a balance between vehicular mobility and pedestrian safety, while maintaining, as much as possible, a continuous connectivity through the urban region.

Then At larger scales, accommodate higher-speed mobility with Multi-Way Boulevard (p. 55) that combine mobility with safe paths and crossings for pedestrians and bicycles. Where the highest speeds are required, use Mobility Corridor (p. 30) with grade-separated pedestrian and bicycle paths, and crossings at no more than 400 meters. At smaller scales, create Sanctuary (p. 66) with Short Lanes5 and Shared Space Lane (p. 60).