Among the Million Plus urban agglomerations/cities, there are three very large cities with more than 10 million persons, known as mega cities. The descending order of the mega cities as per their population size according to Census 2011 is Greater Mumbai UA (18.4 million), Delhi (16.3 million) and Kolkata (14.1 million). The largest urban agglomeration in the country is Greater Mumbai followed by Delhi. The population of Chennai UA is 8.69 million.