Palar , is a river in southern India. It rises in Nandi Hills, India in Kolar district of Karnataka state, and flows 93 kilometres in Karnataka, 33 kilometres in Andhra Pradesh and 222 kilometres in Tamil Nadu before its confluence into the Bay of Bengal at Vayalur about 100 kilometres south of Chennai. It flows as a Guptagamini for a long distance only to emerge near Bethamangala town, from where, gathering water and speed, it flows eastward down the Deccan Plateau. The cities of Ramanaickenpet, Vaniyambadi, Ambur, Gudiyatham, Vellore, Melvisharam, Arcot, Walajapet (Anaicut), Kanchipuram, and Chengalpattu are located on banks of Palar River. Of all the total of seven tributaries, the chief tributary is Cheyyar River.