Usually on each fifteenth day of Full Moon Day of each month as per the Vikram Samvat, year of Indian Hindu calendar, Ambaji celebrates a spontaneous Religious Fair and Festival with "Lok Mela" and the big mass of devotees use to come here to worship Maa Ambaji on each day of Poornima during the year.
But on the fifteenth day ( Full Moon Day ) of the months of Asho, Kartik, Chaitra & Bhadrapad , the Spirit of Festival and Religious Fairs increases at their peaks, due to the significance of these holy days in the worship of Shakti Swaroopini Mata Ambica. The people and devotees also enjoy all these Four Festivals of purnima, with Darshan, Ohm Havan and Traditional Garba Dances. Moreover, the cultural shows of Gujarati Bhawai, a purely ancient folk dance and "Play of Gujarat" is also the prime attractions of these festivals. More specifically to say Bhadrapadi Purnima is the main festival when a big fair of devotees is spontaneously done here in Ambaji and more than 15 lakhs of devotees use to come to worship Maa Amba on this eve and thousands of them come here in community like Padyatri Sangh with the spirit of faith simply by walking from far distant areas situated even at the other ends of Gujarat and from all parts of India. Hundreds of such Padayatri Sangh use to come here to celebrate a Big Religious Fair of Shri Ambaji Mata.