Controlling growth Chinese urban planners have long known that it is difficult to control all the political, social, and economic factors in urban growth, so in all cities, large and small, the central or local authorities would include more space within the city walls than was immediately necessary.
成長管理中國城市規劃者很早就知道，城市受經濟、政治、社會因素影響，規模不易掌握。因此為了應付都市無限制膨脹，不論平地上規劃起來的國都、省城，或是人民先聚集、而後形成的聚落，築城的人往往都會把城池圍得比需要大很多。