Mahashivratri alias Shivaratri means 'the night of Shiva' has great significance in Varanasi, as the place is believed to be the abode of Lord Shiva. It is the night on which Lord Shiva is said to have performed the Tandava Nritya - the dance of primordial creation, preservation and destruction. The festival falls on the thirteenth or fourteenth day of the dark fortnight of Hindu month of Phalgun (usually in the month of February/ March). On this auspicious day all the temples, especially the Shiva temples are elegantly decorated. 

Kashi Vishvanath temple is the main center of religious activity and worship at Varanasi during the Shivaratri festival. The major attraction is the marriage procession of Lord Shiva from the Daranagar Mahamrityunjaya temple to the Kashi Viswanath Temple. On the festival day, the Shivalingam is bathed in every three hours with the five sacred offerings of a cow, called the panchagavya which includes milk, sour milk, urine, butter and dung. Then the five foods of immortality i.e milk, clarified butter, curd, honey and sugar are offered. Even though Dhatura and Jati are poisonous fruits, it is also offered as it is believed to be sacred to the Lord.

Devotees observe fast throughout the festival day and at the end of dawn, they take a holy dip in river Ganges and gather at the Shiva temple. They offer milk, curd, flowers, coconut, fruits etc. to the lord by chanting the religious hymns 'Om Nama Shivay' and sing bhajans. Mahashivratri is said also considered as the festival of women. Unmarried women pray to the Lord to get a husband like him and the married women pray for the welfare of their husbands and sons. On this day, they prepare various sweet dishes made out of coconut, to offer to the Lord. A special drink is prepared on the occasion of Shivarathri with a mixture of milk, almonds and cannabis which is popularly known as Thandai. 

According to Hindu mythology, there are many stories regarding the origin of Mahashivaratri. One of the story has it that, during the churning of the ocean of milk (Samudra Manthanam) by Devas (Gods) and Asuras (demons) to obtain amrita (water of immortal life), a pot of poison appeared from the ocean. When the Gods frightened that this poison would destruct the whole world they seek the help of Brahma, Vishnu and Shiva. In order to protect the entire universe from darkness, Lord Shiva swallowed the poison, which left a dark blue mark on Shiva's throat. Shivratri is celebrated to mark this occasion.