The church in Llanddetty was probably erected in the 13th century. In its interior was found a pillar stone from the ninth century, and although its original location can not be determined with certainty, the call of the name of the early Christian saint, location on the river and morphology of the churchyard cemetery, indicate the beginnings of the temple in the early Middle Ages. In 1878, the building underwent a thorough renovation, and in 1934 the roof was replaced.
The church is a simple and small, aisleless building on a rectangular plan, without a chancel separated from the outside. It was built of dark red sandstone on the southern bank of the Usk River, in an area surrounded by a cemetery. On the south side, in front of the entrance, a porch was placed, and to the east, a second priestly entrance was pierced in the wall. The interior, as in most Welsh rural parish churches, was covered with an open roof truss.
The church has preserved the medieval perimeter walls, but the bellcote on the west side is an early modern addition; also the windows were transformed later. In the recess next to the presbytery portal you can see a inscribed early medieval stone.
Website cpat.demon.co.uk, Church of St Tetti , Llanddetty.
Website parish.churchinwales.org.uk, St Tetti, Llanddetty.