The community of Capel Caeronnen Welsh Unitarian Chapel was formed in 1654, though the current chapel dates primarily from 1846 when it was rebuilt. It was later renovated in 1925. The chapel is in the Vernacular style, entered via a central wooden-boarded door with frosted overlight in the three-bay southeastern gable end. The windows and doorways are square-headed; the fenestration comprises late nineteenth or early twentieth century sash windows with frosted glass and horns. The southwest elevation, formerly the front elevation, has a central date plaque, while the current front elevation has raised rendered lettering which reads 'CAPEL CAERONNEN 1654. 1747. 1846 Adnewyddwyd. 1925'.
Inside the chapel is a single sided wooden gallery enclosed by vertical-panel matcboarding and supported upon circular cast iron columns with plain shallow moulded caps. The ceiling and walls are of white-painted plaster with later coving and ceiling tiles. Bench-style pews are arranged around a central aisle. The five-sided pulpit with canted sides is reached by steps to either side, and is matched by the open sided set fawr with canted sides.

Source: RCAHMW Inventory Documents; CD/Ecclesiastical/SN64SW from O.M. Jenkins

K Steele, RCAHMW, 17 March 2009