Sawan Shivratri which is celebrated as Sawan Shivratri on Chaturdashi Tithi during Krishna Paksha of Sawan month. There are 12 Shivratri in a year which comes in every month but Shivratri of Sawan is special. The month of Sawan is very dear to Lord Shiva. Shiva devotees observe fast for the whole year i.e. monthly Shivratri, but one who is not able to fast for every monthly Shivratri, then he must observe the fast of Shivaratri of Sawan.
Some Shiva devotees have to organize Maha Rudra-Abhishek in the Shivaratri of Sawan. So that by getting the blessings of Lord Shiva, one can get happiness, peace and blessings of Mahodav.
Shivratri falling in the month of Shravan is known as Sawan Shivratri. Since the entire Shravan month is dedicated to worshiping Shiva, the month of Shivaratri during the month of Sawan is considered highly auspicious.
Lakhs of devotees from different parts of North India, especially West Uttar Pradesh, Haryana and Delhi participate in the Kanwar Yatra. Those who start their journey from Haridwar and Gaumukh and with the holy Ganges water brought with them at their place of residence, they perform Jalabhishek of Shivling in temples especially on the day of Shivratri.
The famous Shiva temples in North India, Kashi Vishwanath and Kedarnath temple organize special pujas during the month of Sawan. During the month of Sawan, thousands of Shiva devotees visit Shiva temples and perform abhishek with Gangajal and milk.
Shivratri of Sawan month is more famous in the states of Northern India like Uttarakhand, Rajasthan, Uttar Pradesh, Madhya Pradesh, Punjab, Himachal Pradesh and Bihar. The Purnimanta lunar calendar is followed in these states. In other states of India like Andhra Pradesh, Goa, Maharashtra, Karnataka, Gujarat and Tamil Nadu. Amavasanta lunar calendar is followed in these states. Shivratri coming in these states Shivratri Ashadh is special.
However, the most important Shivaratri known as Maha Shivratri falls during February or March.