Holy Trinity church is located in a large churchyard on the south-west side of Mostyn Street in Trinity Square, in what was the only square in the new resort. It was built in the period 1865-74 in a Decorated Gothic style to designs of George Felton, architect to the Mostyn Estate, in order to accommodate the large numbers of visitors to the resort for which the Church of St George (NPRN 43737) was proving too small; the new church was designed to seat 1200 people. Land was given by the Mostyn family and, from 1859, funds were raised by private and public subscription. Constructed of stone-faced walls and slate roofs, the plan is cruciform and aligned south-east by north-west. It consists of clerestoried nave, north-west tower, side aisles with roofs running in a series of gables at right angles to the nave, transepts, and apsidal chancel to which is attached a south-east memorial chapel. The chapel dates from 1924 and the chancel was extended in 1931-2. Vestries and a hall are attached to the south-west of the nave, linked to the church by a corridor wing, the hall wing at right angles to it. On the north-west is a porch with lean-to roof with centre gabled window and flanking doors against the north-west nave wall. The tower is of three storeys with tall paired lancet belfry openings and a pierced arcaded parapet with octagonal pinnacles. The church is lit through trefoil-headed lights and lancets.
Inside, walls are faced with yellow brick with lacing courses of black or vitreous brick, ashlar mouldings to the windows and arches. The nave is of lofty proportions with timber-framed and boarded roof, principal rafters on ornately carved stone corbels. The side aisles have timber-framed and boarded roofs. The arcades are of Bath stone with thickly carved foliate capitals on mottled grey columns of Anglesey marble. The chancel has ashlar lining and Minton tile paving, partly overlain by marble in 1932. Furnishings and fittings include stalls by Jones & Willis (1882), reredos (1939) and carved wood pulpit (1951). Stained glass includes works by Hardman (five windows in the apse, c.1880), CC Powell (1891), and AL Moore (1887).
Sources:
Cadw Listing description.
R.Haslam, J.Orbach & Adam Voelcker, Buildings of Wales: Gwynedd (2009), p.409-10.

RCAHMW, 25 February 2016