The City Clustering Algorithm, CCA, allows for a test of Zipf’s law for cities of all sizes. We find (ta,tan,ta,tan..) that Zipf’s law is surprisingly valid up to small cities of a few hundred inhabitants. Collaboration with Xavier Gabaix, Stern, NYU. Paper on Zipf’s law for all cities. Published in American Economic Review, August 2011. Below is an image of all the population clusters identified by the CCA in the USA and the CCA cluster around London superimposed with a Google maps.