In addition to the various festivals, Tiruvannamalai celebrates four annual Bhrammotsavams which go on for a duration of 10 days. The most famous of them all is the Kartikai Bhrammotsavam.
Annamalai deepam marks the conclusion of the ten day Bhrammotsavam in the month of Kartikai. On each of these days, the five murthies of Annamalayar, Unnamulaiyaal, Ganapati, Subramanyar and Chandikeswarar are brought in a procession in decorated mounts. Noteworthy among these are the Rishabha Vahana Utsavam on the fifth evening of the festival and the Rathotsavam, on the seventh day.
Before kartikai deepam, Bharani Deepam is celebrated. A a lamp is lit in the main shrine of the temple. This is followed by a fire sacrifice done in front of the shrine of Surya. A small bowl of ghee lighted at this fire is used to light five other lamps representing the five aspects of Shiva.
In the afternoon begin the celebrations of Kartikai Deepam. A portion of this fire is kept inside a container of baked earth and taken to the summit of the mountain. Here, a large copper utensil filled with offerings of ghee and pieces of cloth is kept.
Meanwhile, four of the decorated pancha murthies are brought out from the main shrine of the temple. They are housed in Vimanams in the 3rd prakaram of the temple, facing the flag staff and the Annamalai Hill. The last to arrive is Annamalaiyar who comes out of the second prakaram, dancing with his consort.The deepam is then brought out of the inner shrine and taken towards the Utsavar Annamalayaar. The deepam is brought out in a gait by the bearers and a deeparadanai is offered to the Utsavar.
At the same moment, the lamp on the hill is lighted, even as the crowd breaks into a frenzied cheer, chanting the Lord's name. It is a belief of the people that the deepam is a form of Lord Shiva himself.
With the arrival of the deepam outside, the inner sanctum doors are closed and Annamalaiyaar is to be worshipped only as the beacon until the next morning when the shrine is reopened.
Tens of thousands of devotees throng to this sthalam on the event of annamalai deepam. Special buses and trains are run to Tiruvannamalai and back, to help the devotees who want to catch a glimpse of the deepam on the auspicious day.