St Mary's church lies between Church Street and Sydney Street, set at an angle to Church Street. It is a large nineteenth-century church built on a medieval church site. It was rebuilt by architect Ambrose Poynter in an eclectic Gothic style in 1846-48, of coursed brown stone under slate roofs.
It consists of aisled nave with clerestory, chancel (same height as nave), north-west corner tower, north transept organ chamber, lower chapel at east end of south aisle, and gabled north porch. The tower has an octagonal stone spire with lucarnes, two-light Decorated style windows to the bell stage, stepped buttresses, and a clock. The church is lit through mostly lancet and Decorated style windows, with paired Caernarfon arched windows to the clerestory.
The interior is light and spacious with a camberbeam roof to nave and to chancel. There is no structural division between the two though roof beams to the chancel are heavier and so possibly later in date. Arches to the aisles are broad and have octagonal shafts. There is a west gallery. Stained glass includes works by Ward & Hughes (1885). In the chancel there are memorial monuments by Spence and by E J Physick.
Sources:
Cadw Listing description.
E.Hubbard, Buildings of Wales: Clwyd (1986), p.349-50.

RCAHMW, 30 October 2015