The compound of the temple houses three shrines, out of which are built for Lord Ganesh, One can be found near the foot, another can be found at the shrine of Ucchi Pillauyar, which is situated at the pinnacle and the third one at the shrine of Thayumanavar, which is located between the two. The shrine of Thayumanavar, besides hosting the shrine of Lord Ganesh, also houses the shrine of Goddess Parvathy. One can find many markets and bazaars in the lively locality of Tepakullam that is found close to the foot of Rockfort. In the middle, one finds a stage, which offers boating services. Rockfort can be viewed from each and every part of the city's northern side. The temple is held together by many beams or columns. The lower part contains Mattuvar Kuzhalammai's temple, whereas Thayumanaswamy's main shrine can be seen on the above level. The main temple is surrounded by walls representing the pictures of Durga, Surya, Brahma, Dakshinamurthy, Nataraja and Somaskandar.

Legend has it that a lady by the name of Rathnavati, who was a great follower of Lord Shiva, was pregnant. When she was going into labour, she told her mother to help her by coming there. The Cauvery River was heavily flooded and because of this, her mother could not make it in time as she was stuck. Rathnavathi, a nervous wreck, started praying to Lord Shiva, who pleased by her devotion, helped her with her delivery, by assuming the avatar of her mother. After the delivery was done, the Lord left, and the lady's real mother arrived home. It was then that she realized that it was the Lord himself who had helped her to deliver her baby safely. It is because of this incident, that Lord Shiva is referred to by the name of Thayumanaswamy, here, this word means 'God who acted like a matriarch'. The shrine derives its name from the main idol of Thayumanaswamy. People are of the belief that the city of Tiruchirapalli gets its name via the mythology that is connected to the shrine of Thayumanaswamy. Trishira, who was a demon that possessed three heads, carried out a penance in this place so that God could bless him by fulfilling all his desires. There are also those who go by the theory that the city derive its name from the word- Trishirapuram, this word, in the Sanskrit language, refers to 'three headed', whereas the words 'puram' or 'palli' refer to city.

Regular poojas are performed in the shrine by the priests who reside there. The festival of Chitrai is celebrated here during the months of March and April that lasts for a period of fifteen days. A car festival is organized on the 9th day where a procession is carried out with the idols of the Gods. Also Karthikai is celebrated during the months of November – December.