According to the inscriptions, the temple was in existence even before 1172 A.D. Among several kings who ruled the place Sri Krishna Deva Raya gifted large chunks of lands for the maintenance of the temple. The Zamindars of Narsaraopet Chilakuripet, Amaravathi and several others, have donated liberally for the development of the temple. The height of the Kotappa Konda or Kotappa hill is 1587 feet and the Temple of Sri Trikoteswara Swamy is at the height of 600 feet.

There are three different ways to climb up the hill. Devotees mostly climb up the way which was got constructed by Sri Rajamal Raju Narasimha Rayulu. One of the most fascinating aspect of the hill is that from all angles one could see only three peaks and, therefore, it is called "Trikoota Hills" and the God seated therein is famous as Trikoteswara Swamy.

These three peaks are known as Brahma, Vishnu and Rudra. Anent to the legend, Lord Siva after destroying "Daksha Yagnam" pacified and converted himself into a 12 years old boy and with a great deal of austerity commenced penance as Dakshana Murthy in Kailasam. Then, Lord Brahma and other Gods appraoched and offered prayers to Dakshana Murthy and entreated him to impart the knowledge of "Brahma". Dakshana Murthy accordingly agreed and asked them to come to Trikoota hills where he imparted them the knowledge of "Brahma" making these hills very sacred.

Since Dakshana Murthy observed strict celibacy, no marriages take place in this temple. There is yet another folklore of Salankayya of Yellamanda village who was a great devotee of Lord Siva and eking out his livelibhood by selling firewood. With the result of undivided devotion to the Lingam at Rudra hills he became rich. One day while performing prayers he saw Jangama Devara.

In appreciation of the devotion of Salankayya Jangama Devara daily used to visit his house and consume milk. After some time Jangama Devara disappeared. Salankayya searched for him in every nook and corner of the region and could not find him anywhere. In a fit of disappointment, Salankayya stopped taking any food and water. As the matter stood thus, there lived a cowherd called Sundudu with his wife Kundiri in South side of Trikoota hills.

They had a beautiful daughter called Anandavalli. Her parents became rich soon after her birth. Anandavalli was deeply devoted to Lord Siva and was not interested in her wordly life. She always spent her time in singing the glory of Lord Siva and used to offer prayers at old Koteswara hills she declined to change her way of life and commenced penance for Sri Koteswara Swamy. Pleased with her penance Jangama Devara appeared before her. She came to know Jangama Devara was, none other than a person, who used to take milk in the house of Salankayya. From then onwards she daily visited Rudra hills and after performing celestial bath offered milk and part-took the balance.

Salankayya came to know the presence of Jangama Devara and appraoched Anandavalle and requested her to see that Jangama Devara showers the blessings on him. Anandavalle could not concede the request of Salankayya as she was engaged in her deep penance. After some time, in the hot summer Anandavalle used to visit Rudra hills to perform prayers. One day she collected a pot of water for celestial bath and after keeping it at a safe place proceeded to procure "Maredu leaves". Then, a crow came and sat on the pot, and with its weight the pot fell down throwing out the entire water. Anandavalle became furious and cursed, that no crow should enter the area. Then onwards and till now no crow appears on the Rudra hill.Jangama Devara pleased with her penance appeared and imparted her the divine knowledge. This had in no way deviated her concentration and she further prayed him as God and as well as her Guru. 

Jangama Devara, commisserated at her penance and wished her to lead a wordly life. With his divine power he made her pregnant though she was a spinster. Unmindful of her pregnancy she carried her daily prayers as usual. Aghasted at her deep devotion Jangama Devara again appeared and told that she need not take so many troubles in performing poojas and promised her that he would come to her house where she could do her supplication and asked her to proceed without turning her back.

Anandavalle accordingly proceeded towards her home and Jangama Devara came down from Rudra mountain and followed her. After reaching Brahma hill, Anandavalle lost her patience and turned back. Immediately Jangama Devara reminded of her promise and stopped at Brahma hills and entered the cave of the hill and turned himself into a Lingam. The same sacred place is now called Kotha Koteswara Temple. Anandavalle also stayed there and, in the meanwhile, she delivered a boy. She repented of her action in seeing back inspite of caution given by Jangama Devara and decided to end her life. Within a moment of above thought, assailing her mind the newly born boy disappeared from the scene.

She then realised that her pregnancy and delivery of a boy were of the creation of Jangama Devara to test her reverence towards him. She felt very happy as she got through all the critical trails and became one in the God.