Thirunelli Temple (also Tirunelli) is an ancient temple dedicated to Lord Maha Vishnu on the side of Brahmagiri hill in Kerala. The temple is at an altitude of about 900m in north Wayanad in a valley surrounded by mountains and beautiful forests. It is 32 km away from Manathavady.
No proper records of the exact dates of establishment of temple exist, though it is beyond dispute, that Thirunelli was once an important town and pilgrim center in the middle of an inaccessible jungle valley surrounded by mountains on four sides . There exists documentary proof that Thirunelli at the time of Tamil Chera king Bhaskara Ravi Varma I (962–1019 CE) was an important town and pilgrim center in South India. In the dense jungles surrounding temple, the ruins of two ancient villages can be found. Noted historian V. R. Parameswaran Pillai in his book Thirunelli Documents states that this temple was once an integral part of the early recorded history of Kerala.
The name Thirunelli derives from the nelli, the Tamil/Malayalam and Kannada word for Indian gooseberry of the Amla tree. Veda vyasa wrote the 18 existing Puranas. The Matsya Purana, Skanda Purana, Narasimha Purana, Padma Purana, and many other Puranas and Hindu texts mention the beautiful Vishnu temple as being built by Lord Brahma, located in the picturesque Sahya valley, deep in the middle of forest of unmatchable beauty, and in these texts, it is referred to as "Sahyamalaka Kshetra." According to tradition, Lord Brahma was traveling round the Universe on his hamsa, when he became attracted by the beauty of the area now known as Brahmagiri Hill. Descending on that spot, Brahma noticed an idol, set in an Amla tree. Brahma recognized the idol as Lord Vishnu Himself and the place as Vaikuntha (Vishnuloka) itself. With the help of the Devas, Brahma installed the idol and called it Sahyamalak Kshetra. At Brahma’s request Vishnu promised that the waters of the area would wash away all sins. (Thus, the spring and river near the temple is called Papanasini: “washes away all sins”).