When Sati, attended the yaga no body has cared for her and she felt insulted by the actions of her sisters and parents.Then when her father started abusing her husband she could not control her feelings and scarified herself at the place of yagna by creating agni from earth with her right thumb of her foot.
The temple is located in Trimkomali, or Trincomalee on the eastern coast of Sri Lanka.
The place Trinconmalee means a triangular shaped hill (Tri- cona- malee or malai). There is also a Kali temple which people visit enroute to Shankari Devi temple.
Knowing this Lord Shiva removed one bunch of Jhatha from his head and hit it on the earth.
From that Lord Veerabhadra has born and rushed to yaga spot and killed Daksha by cutting his head.
There are 18 such places and they are called Among these, the Shakti Peethas at Kamkhya, Gaya and Ujjain are regarded as most sacred as they symbolize three most important aspects of mother Goddess viz.