Among the oldest churches in Kerala, St. Mary's Church at Niranam (popularly known as Niranam Valiyapally) in Pathanamthitta is believed to be one of the churches established by St. Thomas, the Apostle of Jesus Christ, in AD 54. This church, rich in history and tradition, celebrates several important feasts each year, attracting numerous devotees.

The church is renowned for its annual feast, held on December 21st, commemorating St. Thomas. Other significant feasts include the Feast of the Assumption of St. Mary (Vaangipu Perunnal) on August 15th, and the feasts of Mar Thoma II and Mar Thoma V on May 10th, whose mortal remains are buried in the church.

The St. Mary's Orthodox Syrian Church, Niranam, has been a symbol of Christian faith in Kerala since its inception by St. Thomas. The church's historical significance is underlined by its connection to the apostle, who established it adjacent to the Sri Thrikpaleswara Hindu Temple of Lord Shiva. The present church building, constructed in 1912, is the fourth structure, replacing one built in 1259. Niranam was a coastal region in the first century, and local legends recount how St. Thomas re-established the church after recovering a lost cross from the river.