Velankanni, officially spelled as Vailankanni (Virgin of Velai, the town), also spelled as "Velanganni" , is a panchayat town in Nagapattinam district in the Indian state of Tamil Nadu, and a parish under Tanjore Roman Catholic Diocese. It is a small town located on the shores of the Bay of Bengal 350 km south of Chennai (Madras) and 12 km south of Nagapattinam on the Coromandel Coast, in Tamil Nadu, India.Once a port that traded with Rome and Greece, the tiny commercial center gradually lost its importance to the larger city of Nagapattinam. The canal built to link this town with Vedaranyam still lies to the west. The Vellayar, a minor branch of the Cauvery River, runs south of the town and discharges into the sea.The town is home to a significant Roman Catholic shrine dedicated to Our Lady of Good Health. Basilica of Our Lady of Good Health:
The church can be traced to the mid-16th century and its founding is attributed to three miracles: the apparition of Mary and Jesus to a slumbering shepherd boy, the curing of a lame buttermilk vendor, and the survival of Portuguese sailors assaulted by a violent sea storm.
Although all three events resulted in the erection of a shrine, it was the promise of the Portuguese sailors that caused a permanent edifice to be built at Velankanni. The chapel was dedicated on the feast of the Nativity of Mary (8 September), the day of their safe landing. More than 500 years later, the festival and celebration is still observed and draws nearly 2 million pilgrims each year.