Church of St Michael

North doorway has a plain square-headed opening, in which is set a probably C17 elliptical-arched frame and Victorian door. Main feature of the church is the fine arch-braced roof to the nave comprising 4 collar trusses with chamfered soffits, the foot of the second truss from the west with a carved face on the south; the fourth truss from the west is of single hammerbeam type consisting of a chamfered and stopped 4-centred arch on moulded beams with moulded bases to wall-posts, sitting on rough stone corbels; above the collar are 2 struts forming a quatrefoil flanked by trefoils: the whole of this truss is renewed above the wall beams; replacement double-purlins and rafters throughout. The chancel has 2 arch-braced trusses like those in the nave and further single trusses are reused in the transepts (that in south transept renewed), suggesting that the chancel originally extended as far as the west side of the transepts; replacement double purlins and rafters, except to north transept where the purlins are old.

Fittings and furnishings all late Victorian: pews (raked at west end and facing southwards to form choirstalls in north transept), reading desk and pulpit (the latter later and bearing the wheatsheaf emblem and "DEO FAVENTE" motto of Duncan Alves, owner of Bryn Bras Castle from 1920-40), low iron screen at west end of chancel and brass altar rail; 3 iron and brass candelabra (for oil lamps) hang from nave roof and similar sconces with "IHC" monogram at west end of chancel. Stained glass in all windows; east in memory of the Revd. James Parry (d.1899), that in south transept to Hugh Barrow Rowlands (killed 1903 in Somaliland), that in north transept (c1903) in memory of members of the Ower and Pritchard families; nave north window commemorates Elizabeth (d.1885) and William Jones (d.1902) and south window Ellen Jane Prichard (d.1889).

Monuments: First World War memorial on south wall of nave (Second World War memorial is in porch) with tablet to Kelyth Pierce Lloyd Williams (killed in action, 1916) alongside; early C19 brass wall tablet to members of the Rowlands family in south transept and brass plate to Hugh Barrow Rowlands (see above) with larger brass tablet to Rowlands on the east wall of the transept "erected by the parishioners of Llanrug, Officers of the Suffolk regiment and friends". Floor slabs at east end of nave to various members of the Rowlands family, Jane (d.1729), William (d.1740) and John (d.1762), latter 2 recorded as of Plastirion. Slate tablets on west wall of vestry record Owen Thomas (d.1762) of Glyn Ifor, who left £5 to the poor of the parish with which a house was built "for their use" at Bryn Crwn and in Welsh John Jones (d.1781) of Bryn y Fedwan, who left £5 to buy white bread for the poor of the parish.

Simple cruciform plan (see History). Roughcast rubblestone with ashlar window tracery; slate roofs with coped verges. Nave has 2-light bar tracery window with hoodmould and quoins to south wall; also in north wall to east of gabled porch, which has slit windows to sides and boarded door (1985) under closed timber-framed gable. Gabled bellcote with single bell superscribed "GRIFFITH WILLIAMS WILLIAM HOWELL WARDENS 1767" to west wall. Roof has one C20 rooflight in south slope and 2 in north; it is half-hipped where it joins the transepts, which have similar windows to those in nave except that they are taller and the quatrefoils to their heads more elongated. Chancel has broad lancet with trefoil head on north; east window similar but broader still and has quoins and hoodmould. Lean-to vestry on south has blocked doorway to east and blocked rectangular window to south.