Here is your short paragraph on Masi Makam:
Observed in the month of Masi (February—March) on the day with the asterism, Makam at Kumbakonam which is regarded as auspicious to celebrate this festival, once in 12 years, when the 9 holy rivers are said to be present in the Mahamakam tank at Kumbakonam.
Pilgrims from all over the country throng here to have a sacred bath in the tank.
The 9 rivers said to be present are the Ganges, Yamuna, Godavari, Saraswati, Narmada, Kaveri, Kumari and two others. These rivers find representation in sculptures in the Viswanathaswami temple at the northern bank of the Mahamakam tank.
Govinda Dikshitar, the minister of the Nayak kings of Tanyavur effected the repair of the tank and constructed 16 temples on its banks.
A sea bath in Setu near Rameswaram and Vedaranyam and the river Svarnamukhi at Kalahasti are also considered equally beneficial. From the records of Nagalapuram, it seems Krishna devaraya witnessed the Mahamakam festival in Saka 1445.