Interior
The nave is covered by a late C19 arch-braced collar roof, the principals rising from wall posts on stone corbels. Rere-arches with fleurons to the C19 windows and the E window has nook shafts. The C19 chancel arch is set on impost corbels, and has two C14-C15 quatrefoils to either side above. The C15 tower arch is tall, of two chamfered orders, rising from the floor level raised 3 steps above the nave. The interior of the tower has a shallow stone barrel vault. The door to the tower stair opens from the S side of the nave. A door to the former rood stair on the N side of the nave, with the gallery opening above. The chancel is of generous width; 3 roof bays, also arch-braced, and 2 moulded purlins. A stone cornice is enriched with rectangular leaves. Remarkably rich encaustic floor tiles. Three steps rise to the altar. Fittings: A dado of panelled oak set across the E wall. The wooden reredos is delicately carved and painted, including a representation of St Cynwyd holding a model of the church, restored 1984. Low wrought iron chancel screen. Oak octagonal pulpit. Plain octagonal limestone font, tapering to a square base, probably medieval. At the rear of the church, 4 late medieval oak pews (a fifth is in the National Museum of Wales). Also an oak parish chest. The six tower bells, by Abraham Rudhall of Gloucester, 1730, were recast and hung in a new frame in 1893 and rehung again in 1953. Glass: E window an Ascension of 1893 by A Saville of London, tower W window, and grisaille in the N and S windows.
Monuments: A good collection of wall monuments. In the nave N side, from the W: (a) incised tapered stepped cross with a crude representation of a chalice at the side, late medieval to C17; (b) Bas relief triple crosses joined with a semi-circle at the base, all raised on a stepped base, similar date; (c) small relief cross pattee, inscribed to Mary Powel, 1671; these found built in to the walls when restoration took place. (d) sandstone wall slab with semicircular top stone, to William Hopcyn, d.1707; (e) Large wall tablet with fluted side pilasters, cornice and urn in semicircular top, to Hopkin Hopkin, d. 1742 and numerous other family members to 1945; (f) Smaller stone tablet with incised fluted pilasters, urn in crest, to Ann ab Gwillim Treharn, both d. 1814; (g) slab with skull and cross bones in a raised crest, to Jenkin Griffith, d.1909; (h) white marble tablet on slate, to David Thomas, d. at Ypres, 1917, etc; (i) Carrara marble sacophagus tablet on slate, to Evan Rees of Gadlys Factory, d. 1923; (j) Marble tablet on slate, crosses at corners, to Catherine Maddock, d.1922; (k) Incised stone inscribed ME.1616 WT.1596 / MM.1608. Also two brasses.
On the S nave wall: (l) tablet commemorating the renovation of the tower in 1931, and (m) a tablet commemorating the Bryncynon Bequest, also after 1931. Also 3 brasses. In the chancel, S wall, (n) a simple slate tablet engraved to Richard Penril Llewelyn, vicar 1841-1891, and his wife; (o) Elegant sarcophagus tablet in marble set against black stone, to Jenkin Thomas Jenkins of Gelly, d.1876. One brass. Also, set in the floor, the famous black grave slab with an inserted brass, a later memorial to Ann Thomas, 'y ferch o Gefn-ydfa'. Under the tower is a series of 6 gravestones of the C17 on, brought in for protection, including those of Ann Thomas and Wil Hopcyn. In the porch, fragments of the earlier building, including a C13 column base secondarily used as a sharpening stone, and a moulding.