Papanasam — literally "destroyer of sins" — is a small temple-and-waterfall complex about 50 km west of Tirunelveli, where the Thamirabarani river drops out of the Western Ghats. The Papanasanathar temple, dedicated to Shiva, sits beside the falls, and pilgrims bathe in the lower pools before darshan.
The river has been dammed just upstream to form the Karaiyar Reservoir; jeep safaris from Mundanthurai sometimes pass through here. The area is gentle and quiet outside festival times — a calm half-day if you want to combine a swim, a temple visit, and an excuse for a drive into the foothills.