Holy Trinity Church was erected in 1841-1842 and licenced in 1842. It was built to replace an earlier chapel, thought to have stood within the castle. In his 1844 Topographical Dictionary of Wales, Lewis describes the church as 'containing 500 sittings, of which 400 are free'. The church is situated at the west end of Church Lane, within a rectilinear churchyard. The church is a Grade II listed building, and the churchyard boundary walls and monuments within the churchyard are also included within the listing.

The church was designed by J.L. Collard of Carmarthen, and consisted of aisleless nave with hammerbeam-type roof of five bays, chancel, south porch and west tower. The nineteenth century tower was plain with a corbelled, castellated parapet and plain louvred bell openings. The building was renovated in 1924-1926, when the nave was given passage aisles by adding square stone piers up to the undersides of the hammberbeams. Renovations also included the extension of the sanctuary and new windows throughout. The east window had stained glass of circa. 1924. There is twentieth century glass in the other five windows. The chancel has a boarded wagon roof and much finely carved circa. 1920 woodwork. Ashlar tracery was added to the tower's bell-openings and the ground floor west window. The tower was widened, with stepped angle buttresses up to bell-stage which has raised angle piers and paired segmental arches under the corbelled parapet. The plain castellation was altered to include stepped corners. A fragment of good quality circa. 1860 glass in the tower suggests that the original tracery may have been re-used.The stem font is Art Nouveau with a beaten copper cover.

Sources include:
Cadw, 2012, Listed Buildings Database
www.genuki.org.uk

N Vousden, RCAHMW, 15 October 2012