Govardhan Puja: Lord Krishna had lifted the hill to provide shelter from to villagers from rains.
Govardhan Puja, also called Annakut or Annakoot, is a Hindu festival dedicated to Lord Krishna. Annakoot, which translates to "a mountain of food", is offered to the lord as a mark of gratitude. According to Bhagvata Puran, Lord Krishna had lifted the Govardhan Hill to provide shelter to the Vrindavan villagers from torrential rains. Devotees offer a mountain of food, metaphorically representing the Govardhan Hill, to Lord Krishna as a ritual remembrance and to renew their faith in taking refuge in God.
The Annakut festival occurs on the first lunar day of Shukla Paksha (bright fortnight) in the Hindu calendar month of Kartik, which is the fourth day of Deepavali (Diwali).
A story mentioned in the Bhagavata Purana traces the origin of the Govardhan Puja. Cowherds living close to Govardhan in Uttar Pradesh used to celebrate the autumn season by paying respect to Indra, the God of rain and storm. Krishna, however, desired that the villagers worship Mount Govardhan instead as it provides natural resources to the villagers and was responsible for the natural phenomena that occur in the city of Gokul. When Indra saw the villagers' devotion diverted away from him and toward Krishna, he initiated thunderstorms and heavy rains in the city. To protect the people from the storms, Krishna lifted the Govardhan mountain on his little finger and provided shelter to the people and cattle of the city. When the people of Gokul remained unaffected, even after 7-8 days of continuous storms, Indra accepted defeat and stopped the storms. This day is therefore celebrated as Govardhan Puja and respect is paid to Mount Govardhan and Lord Krishna and Govardhan has since become a major pilgrimage site in Braj for the Krishna devotees.