According to Hindu calendar, Chhath Puja is celebrated on the sixth day of Kartik month. Chhath Puja, also known as Surya Shashti, is a bathing festival followed by a four day period of abstinence and ritual purity. This festival is widely observed in Bihar where a large number of sun temples are present. These sun temples are generally surrounded by a surajkund, also known as sacred pool of sun, which constitute of the place of worship for the devotees. Traditionally, Chhath Puja is performed by women, however large number of men also register their presence during this festival.
Chhath Puja is a four-day long strict and spiritual observance. The first day of the Chhath Puja includes taking a dip in the holy river Ganges. People also take the water of Ganges to their home to perform special offerings and rituals. Houses are thoroughly cleaned on this day. The second day of Chhath, also known as Kharna, involves devotees to observe a day long fast which is broken in the late evening after performing the worship of Mother Earth. The offerings to the God include rice pudding (kheer) and fruits, which is distributed among family members and friends. The third day of Chhath goes in the preparation of the prasad (offerings) for the evening offerings, also known as Sanjhiya Arghya.
In the evening, large numbers of devotees gathers on the banks of river Ganga and make offerings (Arghya) to the setting sun. The folk songs are played in the evening displaying the culture and history of Bihar. Nowadays popular Bollywood songs are remixed and played during this occasion. The night of the third day witnesses a colorful event known as Kosi. A canopy is made from five sugarcane sticks and lighted earthen lamps are place inside canopy along with baskets filled prasad. On the fourth and final day of Chhath, family members and friends go to the banks of river before sunrise and make offerings (Aragh) to the rising sun. After this ritual, devotees break their fast and distribute prasad to neighbors and relatives.