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An urban agglomeration is defined as "a continuous urban spread constituting a town and its adjoining outgrowths, or two or more physically contiguous towns together with or without outgrowths of such towns". An urban agglomeration must consist of at least a statutory town and its total population (i.e. all the constituents put together) should not be less than 20,000.
List
Below is a list of urban agglomerations in the state of Tamil Nadu, with a population of 1 lakh and above based on the 2011 census of India. Cities in bold are declared Municipal corporations.