During the period of Chand kings, Nanda Devi worship took the shape of a fair. Prior to that, Nanda Devi was being worshipped, but at that time only an idol of Nanda Devi used to be worshipped. The custom to make two idols started from the period of Baj Bahadur Chand. Even today, only one idol is prepared in the remote villages. The reason for this addition appears to be because the goddesses Nanda and Sunanda together took birth as princesses in the royal family and to mark this new reincarnation, the practice of celebrating a festival for both sisters together was introduced in which a story from their life is enacted.