Nag Panchami is the festival of snakes. Offerings are made to snake images and snake charmers flock into the city with real snakes to celebrate the festival in respect of Serpent Ananta, upon whose coils Lord Vishnu rests The devotees collect hundreds of cobras, place them in earthen pots and worship them to the accompaniment of folk dances and song. Later they are carried in processions of bullock carts and chariots.
In Mumbai, cobras are venerated and fed sweetened milk, usually by women. On the following day they are released back into the fields from where they were captured. The victory of Krishna over the Kaliya snake is also remembered on this day. For this reason, Krishna is known as 'Kaliya Mardan'.
The festival celebrates during the rainy months. It is believed that the festival is to counter the increased possibility of snakebite during this time. People visit temples specially dedicated to snakes. Shiva temples are also crowded during this festival, as snakes are considered dear to him.