Dev Deepavali is the Festival of Lights of the Gods. This is celebrated every year in certain parts of India on the full moon of the Hindu month of Kartika (November - December) and celebrated fifteen days after Diwali. According to Mythology, the gods are believed to descend to Earth to bathe in the Ganges on this day. The devotees take a holy bath in the Ganges and offer oil-lighted lamps to Ganga in the evening.