Chennai Listeni/ˈtʃɛnaɪ/ (formerly Madras Listeni/məˈdrɑːs/) is the capital city of the Indian state of Tamil Nadu. Located on the Coromandel Coast off the Bay of Bengal, it is the biggest industrial and commercial centre in South India,[6] and a major cultural, economic and educational centre. Chennai is known as the Detroit of India for its automobile industry.[7] As a growing metropolitan city in a developing country, Chennai confronts substantial urban pollution, traffic congestion, poverty, overpopulation, and other logistic and socioeconomic problems.The area of Chennai (Chennai Corporation) was expanded in September 2011 from 176 Sq Km to 426 Sq Km, with a subsequent redefinition bump from 4.6 million to 8.7 million people inside the new city limits during the march 2011 census. The urban agglomeration may now be considered the city itself (though suburbs do exist beyond the new expanded limits, the metropolitan definition has yet to be updated), currently ranked as fourth most populous metropolitan area in the country and 31st largest urban area in the world.