The most sacred and important cave is known as Olasuni Gumpha or Sidha Gumpha where Santha Arakhita Das practiced “Omkara Yaga”, is the original cave of the Goddess Olasuni. After the Mahaparinirvan of Santh Arakhita two rooms in a single sturcture are built on the cave.
The roof of the structure is on Pidha deula styel that is Tree Pidha (three steps ). One above of the roof Amlaka, Khapuri and Dadhi Kalasa with Ayudha Chakra also constructed, represent like a Mandira . Inside the room there is a Mandapa where the sacred palm leaf manuscripts called “ Mahimandala Geeta ’’ composed by Santha Arakhita is kept inside a wooden bimana and it is still in active worship.
Inside the room there is a small door in the gate way inside to the cave . The size of the total structure measure 31 feet 10 inches in length and 16 feet 3 inches in breath. The inside of the two rooms measures, 1st room 17 feet in length and 10 feet 7 inches in breath where as 2nd room measures 10feet 7 inches in length and 8 feet 1 inches in breath.