St John's church is situated in a prominent position on the hillside above the earlier settlement of Cymmer centred round the eighteenth-century chapel. It was built in 1888-9 by the architect E.M. Bruce Vaughan of Cardiff on land of the Bedw Estate to serve the population working at Cymmer Colliery Steam Coal Seams which operated from 1877. The services originally alternated between the English and Welsh languages.
The church is built in Early English style Gothic of rock-faced, occasionally snecked, sandstone with ashlar dressings. It consists of nave, chancel, and north and south aisles, under a single unbroken, steeply-pitched, gabled roof now of artificial slate and which incorporates the base of a former fleche. The double-cross gabled vestry wing at the north-east is a two-storey structure because the ground level falls away and has enclosed stone flight of steps to door. The windows are mostly two or three light windows, simple lancets or geometric tracery interspersed with slim but deep buttresses to the south and north. The east and west windows have more decorative geometric tracery, small triple lancets in gable apexes. The north churchyard boundary wall is of rubble sandstone with decorative iron railings and gates with steps east and west.
The interior is lofty with unusual timber nave aisle arcades of painted wood comprising octagonal piers supporting transverse arches and elaborately pierced spandrels. The wide and high chancel arch has a wooden 'Insole' screen of 1909 with heavily carved and painted bressumer. The unusual painted stone pulpit incorporates carved putti and saints in roundels. Stained glass includes windows by Kempe and Tower studio.
Source: Cadw Listing description

RCAHMW, 15 December 2014