Spreaded across 6.2 acres of land, Mahamaham tank is most sacred pilgrim spot where Mahamaham is celebrated once in every 12 years. There are 20 holy wells in the tanks each representing holy rivers which flow across India. As per legend, Lord Brahma was approached by sacred rivers stating that people wash their sins in us and we want to rinse their sins from us and so provide us with a solution. Lord Brahma asked them to confluence in one place near Kumbakonam when Jupiter enters the Leo Sun sign and get rid of the devotees sins. This incident is termed as “Masi Mahamaham” which occurs during February or March.
During Mahamaham, Gods and Goddesses from all temples in and around Kumbakonam are taken in procession to the tank. Then along with devotees, saints etc, the Gods and Goddess idols also dipped in the tank water of Mahamaham tank. After the holy dip, devotees worship all Shiva Temples in Kumbakonam.