Sasthamcotta Shri Dharma Sastha temple is one of the five ancient Sastha temples in Kerala- AchanKoil, Aryankavu, Kulathupuzha, Sasthamcotta and Sabarimala. The concept of Dharma Sastha represents the unison of Vaishnava and Saiva beliefs. The presiding deity of the temple is Shri Dharma Sastha, accompanied by his consort ‘Prabha’ and son ‘Sathyaka’. The legend of this temple stretches beyond the period of the Ramayana (Thretha Yug).
It is believed that Shri Rama along with his wife Sita, brother Lakshmana and the whole vaanara sena, on their way back to Ayodhya after the victory over Ravana, stopped at Sasthamcotta to pay their reverence to Shri Dharma Sastha. Shri Rama offered ‘pithru tharpan’ on the banks of the Sasthamcotta Lake, the water of which is supposed to be identical to ‘Surya Raga Theertha’ of Manasa Sarovar. Lord Rama then deputed the chief architect of his vanara (monkey) team, ‘Neelan’ to serve his host. Neelan is believed to be the predecessor of the prevailing monkey clan in this temple.