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Recently I had been to this beach when I went to Chennai for US VISA :
It is the Marina beach that lies to the east of Chennai (Madras) at Kamarajar Road, 3 Km from the City Centre. The fine sandy beach said to be the longest beach in India and one of the longest in Asia, extends to a length of 13 Km, from Fort St. George all the way to Mahabalipuram. There is a drive along the beach fringed with palms and casuarinas running the whole length of Chennai.