Half as many people will not support half as many enterprises In a given geographical territory, half as many people will not support half as many such enterprises spaced at twice the distance. When distance inconvenience sets in, the small, the various and the personal wither away. Jane Jacobs, The Death and Life of Great American Cities densitydistancegeographybusinesseconomics
Urban form and grain One square mile of different cities' street networks, held at the same scale to compare the urban form and grain. Geoff Boeing, The Right Tools for the Job Cityspace series mapscities