The largest celebration of this Hindu festival takes place in Mathura and Vrindavan

Since He was born at midnight, devotees observe a fast and sing devotional songs for him as the clock strikes twelve.
Devotees then break their fast and share food and sweets
Lord Krishna was born on the eighth (ashtami) day of the dark fortnight in the Bhadrapada month (August–September) in Mathura
The birth of Lord Krishna, Janmashtami, is celebrated with pomp and fervour throughout India.
Devaki and Vasudeva were married with a lot of fanfare, however, a prophecy said that the couple’s eighth son would cause Kansa’s downfall.
When the couple’s eighth child, baby Krishna, was born, Vasudeva managed to rescue the baby and gave him to Nand Baba and Yashodha in Vrindavan.