Many legendary stories have been obtained over the centuries regarding the Temple and that of Mata Chhinnamasta.
In Shri Markandeye Purana it is mentioned that after slaying thousands of Asuras (demons from the underworld per Hindu mythologies) Jaya and Vijaya- the two ‘sahyagonis’ of Maa Bhagwati wanted to gulp more blood. Their thirst for drinking blood was still not over even after assassinating many Asuras. When Mata Bhagwati came to know abot their thirst, She cut-off Her own head and offered Jaya and VIjaya blood and quenched their thirst.
From then onwards, this incarnation of Devi Bhagwati came to known as Maa Chhinnamastika or Mata Chinnamasta (meaning cutting off head).
Another popular legend of Mata Bhagwati centers on the shrine. It is said that once the deity along with Her divine attendants were taking a bath in the river and they took much time to bathe. Meanwhile, the attendants grew hungry and prayed to Mata Bhagwati for food. The merciful Goddess cut off her own head and offered Her attendants with Her own blood that sprinkled to their mouths from the cut throat of the Goddess. The deity is worshipped in this form too.
This is the transcendence of Mata Bhagwati to Goddess Chhinnamasta or Prachanda Bhairavi.
Yet another Mythologu says that Lord Shiva had a dance of destruction (Rudra Tandava) carrying half burnt body of goddess Sati after goddess Sati’s self-immolation. To stop the dance of destruction performed by Lord Shiva, Lord Vishnu threw His Chakra (Sudharshan Chakra) on Goddess Sati’s body which dismembered Her body into 52 parts. Each body part or ornament of Goddess Sati that fell on different places of the earth, and is the places where the Adi Shakti temples are built.
And it is said that the head of Goddess Shakti fell at the place where Chhinnamasta temple is has been built.