Naag Panchami is the day set aside for the naag. It is celebrated on the fifth day of the full moon and falls usually in late July or early August.
For Hindus, the naag is the giver of rain. On this day, devotees paste pictures of the naag over their doorways and pay homage. Offerings in the form of food are left out in the yards and fields for the snakes. Devotees throng Taudaha in Kathmandu to worship Karkotak Naag. It is believed that the serpent king Karkotak Naag moved to this dwelling after Manjushree drained the Kathmandu Valley, which used to be a lake, by slicing a passage through the hills to make it habitable.
People aslo visit Nagdaha and the public wells and stone spouts to offer puja.
It is also believed that in at one time in history, the naags had stopped the rains in Nepal. However, the king at that time, a tantric, used his power to make naags release the rains. He succeeded in his mission, but also honoured the power of naags on that day.