Velankanni (or Vailankanni) is a famous pilgrimage town in Tamil Nadu, India, known for the Basilica of Our Lady of Good Health, a significant Roman Catholic shrine where Our Lady of Good Health (Mary) is venerated, attracting millions of pilgrims annually as the "Lourdes of the East" due to reputed apparitions and miracles. Key events include apparitions to a shepherd boy, healing of a vendor, and rescue of sailors, leading to the shrine's establishment, its elevation to Minor Basilica status by the Pope, and its importance as a major Christian site.