The long Amaravati River begins at the Kerala/Tamil Nadu border at the bottom of Manjampatti Valley between the Anaimalai Hills and the Palni Hills in Indira Gandhi Wildlife Sanctuary and National Park in Tirupur district. It descends in a northerly direction through Amaravathi Reservoir and Amaravathi Dam at Amaravathinagar. It is joined by the Kallapuram River at the mouth of the Ajanda valley in Udumalaipettai. Through Dharapuram and Aravakurichi it joins with the Kaveri at Thirumukkudal, about from Karur.