The Holy Cross Church at Mattancherry — known to the Catholic community of the Diocese of Cochin as the Coonan Kurisu Palli (Bent Cross Church) — is the original site of the historic Coonan Cross Oath of 3 January 1653. Established by Portuguese missionaries around 1550 as a chapel of the Holy Cross, it is a Latin Catholic parish under the Diocese of Cochin.
On that day, a vast gathering of St. Thomas Christians tied a long rope to a standing cross on the northern side of the church and took the oath that shaped the future of the Church in India. The site stands today as a venerated pilgrimage destination of the Diocese — a place to remember, to pray and to give thanks for the heritage of faith preserved through that hour.