St Rhian's Church is situated within a polygonal churchyard, at the centre of a farmyard complex, about 100m north-east of Llanrhian of crossroads. First edition Ordnance Survey mapping depicts a circle of orthostats (c.600m diameter) surrounding the churchyard, although these have been interpreted as rubbing stones. The site is thought to be early medieval in origin. It was alienated by Bishop Wilfred of St Davids between 1085 and 1115, having previously been an episcopal possession. There are at least three possible chapel sites within the parish.

The cruciform church is a Grade II* listed building, constructed from random rubble stone with low-pitched slate eaves roofs. It consists of 2-bayed chancel, 3-bayed nave, north and south tarnsepts from the nave central bay, and 2-storey west tower. The tower is 13th or 14th century, with a slate saddleback roof with crowsteps and obelisk finials added 1836. The octagonal oolite font bowl dates from around 1500 and bears the arms of Sir Rhys ap Thomas. The church was rebuilt to its present cruciform plan in 1836. The nave and transepts form a perfect cross, the transepts opening to the nave central bay. The nave has broad transepts with raking battlements and crude shoulder and apex finials. Slate coping beneath battlements is slightly returned like a schematic open pediment, echoed by similar slate hood over 3-light traceried pointed windows. Matching pointed-head 2-light windows each side of transepts and elaborate red brick star-shaped chimney at the north-east angle of nave. There are a number of medieval consecration crosses built into the facework. The plain chancel is thought to have been remodelled after 1845. The chancel has one hoodmoulded flat-headed 2-light south window and 4-light east window. Late 18th and 19th century tomb slabs are attached to the external south wall. The church was restored in 1891, and the stone traceried windows and internal alterations by J P Seddon and J Coates Carter date to this time.

Sources include:
Cadw, Listed Buildings Database
Cambria Archaeology, 2000, Carmarthenshire Churches, gazetteer, 48
Cambria Archaeology, 2003, Early Medieval Ecclesiastical Sites Project, Pembrokeshire gazetteer

N Vousden, 5 January 2018