Problem
Any part of town—large or small—which is to be identified by its inhabitants as a precinct of some kind, will be reinforced, helped in its distinctness, marked, and made more vivid, if the paths which enter it are marked by gateways where they cross the boundary.
Solution
Mark every boundary in the city which has important human meaning—the boundary of a building cluster, a neighborhood, a precinct—by great gateways where the major entering paths cross the boundary.
Related Patterns
… at various levels in the structure of the town, there are identifiable units. There are neighborhoods — Identifiable Neighborhood (14), clusters — House Cluster (37), communities of work — Work Community (41); and there are many smaller building complexes ringed around some realms of circulation — Building Complex (95), Circulation Realms (98). All of them get their identity most clearly from the fact that you pass through a defined gateway to enter them — it is this gateway acting as a threshold which creates the unit.
Make the gateways solid elements, visible from every line of approach, enclosing the paths, punching a hole through a building, creating a bridge or a sharp change of level — but above all make them “things”, in just the same way specified for Main Entrance (110), but make them larger. Whenever possible, emphasize the feeling of transition for the person passing through the gateway, by allowing change of light, or surface, view, crossing water, a change of level — Entrance Transition (112). In every case, treat the main gateway as a starting point of the pedestrian circulation inside the precinct — Circulation Realms (98) …
Alexander, Christopher. A Pattern Language: Towns, Buildings, Construction. Oxford University Press, 1977, p. 276.