Rubble stone walls formerly plastered. Fine 1885 open wagon roof of 7 bays. Deep splayed segmental-pointed window reveals. Projecting corbels along W wall. Segmental-pointed tomb recess each side of nave. Three mural stairs suggesting two screens, each side of transept arches: one stair in S wall entered from pointed doorway, one opposite, entered from N transept, and one in E wall behind pulpit, with pointed doorway. Niche and piscina also behind pulpit. Font of 1887 by Middleton, made by H. Hems. Oak inner S porch, 1964, probably by A.D.R. Caroe. Hexagonal oak pulpit, 1910, by W.D. Caroe. Segmental pointed N doorway to tower, 1713 oak door inscribed `Haec est domus dei porta coeli''. Outer N doorway is finely moulded with hoodmould and tower basement has deep pointed arches each side and quadripartite ribbed vault. Winding stair to tall 2-storey ringing chamber and then bell-loft, open right up to top of spire, the spire carried on 8 pointed arches.
Transepts and chancel arch have matching big triple rounded shafts to jambs, rising from large chamfered bases. These appear to be C12 or early C13 but segmental-pointed broad arches are early C14, exceptionally low and broad to chancel. S transept, now Lady Chapel, was Mansel of Muddlescombe chapel in C18. Collar-truss roof, possibly of 1767, as Rev John Mansel plaque in NE corner records a rebuilding then. Ashlar Gothic screen of c1960, altar 1963. S wall has 2 tomb recesses with carved tomb-slabs: to left with low-relief face of a lady, to right with incised foliate cross. Moulded piscina to left. Fine carved male effigy on tomb slab to right of altar. N transept, now organ chamber and vestry, was the Llechdwnni chapel in the C18. Exceptional carved organ-case by Thomas Warne, 1762, brought from St Mary, Swansea, 1907. High chancel roof with 8 arch-braced collar trusses, possibly C17. Windows have deep splayed reveals and moulded segmental-pointed rear arches. Moulded stepped sill-courses below. Tomb recess each side. Tracery of one blocked C14 N window visible, 2-light cusped Y-tracery, the other plastered over. Centre pointed N doorway to chantry with 2 delicate C14 stone lamp brackets. Late C17 bolection-moulded plaster panel above, and traceried small roundel light from chantry set high. N chantry chapel was 2-storey, became vestry in 1725, restored 1975. Squint, piscina and fine corbelled mural stair in S wall, jamb of medieval window in E wall. C18 collar-truss roof. Chancel S has very fine triple sedilia and piscina, earlier C14. Sedilia with octagonal piers threaded through stone bench and triangular heads with cusped spandrels. Piscina has cusped ogee tracery, triangular hood and small lamp bracket. E wall ashlar arcading of c1960, fine C15 alabaster carving of Virgin and Child on corbel to right. Later C20 oak stalls and reading desks. Slate floor.
Stained glass: W 5-light, 1960, by Celtic Studios, E 5-light 1939 and S transept S window, 1930s, both by C.C. Powell.
Memorials: Nave N: Rev. C.W. Bowen (d1835) by D. Mainwaring; nave S: Thomas Pardo (1730s), Baroque. N transept: T. Evans, 1858, by Joseph Edwards. Chancel N: J. Clement (d1831) by Tyley; daughters of Thomas Kymer, builder of first canal in Wales 1766-8, c1830. Chancel S: Catherine Thomas (d1809) by D. Mainwaring.