The Aranmula water regatta conducted on the Pamba River in front of Sree Parthasarathi temple in Pathanamthitta district of Kerala every year from July 15 to October 2 is the oldest river festival has its origins in the 18th century. The 80 days long river festival brings together 51 large traditional snake boats called Palliyodam three times a year – on Thiruvona Thoni, Uthrittathi Vallamkali and Ashtami Rohini Valla Sadya respectively – at the same location. Around 5,000 oarsmen and 510 folk singers, all wearing the traditional dress, take part in the performance. The oarsmen paddle the boats in unison to the accompaniment of songs (Vanchippattu). The Uthrittathi Vallomkali (boat race) held during the Onam season (August-September) with an average of 110 people rowing each snake boat is the largest traditional water sport in the world.
Another essential component of the festival is Vallasadya, a community meal for a total of 5,00,000 people including the oarsmen and other participants during the season – 1,00,000 people on Ashtami Rohini, the birthday of Lord Krishna, and another 4,00,000 during the season.