The Ayyappa temple at Sabarimala was opened on Saturday afternoon for the five-day monthly rituals in the Malayalam month of Kanni that begins on Sunday.
Melsanthi T.M.Unnikrishnan Namboodiri opened the sanctum sanctorum at 5 p.m.
Hundreds of devotees from southern India trekked the holy hills, braving heavy rain in the forests, to offer prayers at the temple in the evening.
The rituals will begin at the Ayyappa temple with the Tantri performing Ashtadravya Maha Ganapati Homom on Sunday morning.
Kalabhabhishekom will be performed at the temple prior to Utchapuja on Sunday. Padipuja, Ashtabhishekom, Udayasthamanapuja, and Pushpabhishekom are the other major rituals to be performed at the temple on all the five days.
Laksharchana will be performed at the temple on September 19, Yatheendranath, Devaswom Administrative Officer, said.
Sahasrakalasabhishekom will be performed at the temple prior to Utchapuja from September 18 to 21.
The Ayyappa temple will be closed after Athazhapuja on September 21 evening.