Bogar Samadhi is inside the hill temple, south west of the sanctum sanctorum in a narrow cave like the corridor. It is believed that there is an underground passage here that goes straight to the foot of the main deity, Lord Murugan. Actually, Bogar himself constructed this and went into Nirvigalpa Samadhi here. He is last seen by his disciples at this entrance.
In the shrine is present the idol of Bhuvaneswari Amman and a Shiva lingam made of Maragatha stone (when you visit, ask the priest specifically to show them) worshipped by Bogar. Below these deities is the underground passage where Bogar went into samadhi. Now this has been covered completely without any indication of such a passage. One of our relatives couple who had been childless for several years had been advised to visit this shrine. They did and got the baby as well. During this trip they had come with the child and sat in the shrine again as thanks-giving.