A nave and chancel church demonstrating a number of different building phases. The nave, constructed from well-cut ashlar, appears to represent the earliest, 12thc., phase of building. A vaulted chancel was added to the E end in the 13thc. Changes made in the 15thc., included the revaulting of the chancel, possibly due to the insertion of an elaborate tomb in the S wall. The W end of the nave was also extended, and a fortified dwelling incorporated into the W wall. In the 18thc. Captain (later Sir) Edward Doddington remodelled the church for use as a place of protestant worship until a new church was built in the village in 1711–6. He was also responsible for the construction of a large house and bawn (defensive wall) to the W of the church. The site is now in the care of the Department of the Environment Northern Ireland (DOENI). 12thc. features comprise what appears to be blind arcading on the E wall of the nave, antae on NE and SE angles, a moulded S window, and a carved fragment, now lost.

A monastery was founded at the site by St Nechtán in the 7thc. A group of stake holes located during archaeological excavation at the W end of the church suggests some earlier building activity. At some point in the 12thc. the Ó Catháin family took control of the territory of Glenn Geimin in which Dungiven is located, and it seems probable that they were responsible for the foundation of the Arroaisian House at the site, first mentioned in 1207 (MacCarthy 1893, 247). The 13thc. addition of a fine, vaulted chancel is also most likely due to Ó Catháin patronage. The Ó Catháin’s surrendered Dungiven in 1602, when the area was granted to the Skinners' Company of London.

The window in the S wall of the nave is closely paralleled by a window in the nave of Banagher church, just one and a half miles away, and it is tempting to suggest that the original W door (now lost) may also have taken on the peculiar shape found at Banagher, and more distant Maghera. Unique to Dungiven however, is the manner in which the surviving eastern angles of the nave are treated, with flat pilasters and three horizontal bands extending across part or all of the original E wall. Examples of more elaborate strip work may be seen in the gable of the N porch at Cormac’s Chapel, Cashel, Tipperary, and is found in a number of Anglo-Saxon structures, where it is suggested that it mimics earlier wooden models.

The arched recesses in the E wall of the nave must represent blind arcading, again a feature relatively rare in Irish Romanesque but found at Ardmore (Waterford), Cormac’s Chapel, and Ardfert (Kerry).