Holy Trinity Church, 6 Seahill Road, Craigavad, Holywood, BT18 0DE

Holy Trinity Church is a double-height Church of Ireland building constructed in 1857 to designs by Francis Farrell of Dublin, with subsequent extensions by William Batt in 1886. The church is aligned southwest to northeast on the west side of Seahill Road, Craigavad.

The building is rectangular in plan with a three-stage tower to the southwest, a later chancel to the northeast, a side chapel added in 1921, a vestry from 1975, and a lean-to vestibule from 1976 to the southwest end. The roof is pitched natural slate with roll-topped clay ridge tiles and stepped ashlar sandstone verges on carved kneeler stones with quatrefoil detail. Gabled finials crown each end, with a cross finial above the chancel. Rainwater goods are profiled aluminium set on projecting stone eaves.

The walls are primarily uncoursed basalt rubble with some isolated snecking, supported by offset buttresses. Sandstone dressings include the plinth, cill course, quoins and offsets. Windows are stained and leaded within chamfered sandstone surrounds. The nave is lit primarily by paired lancets with a triple lancet at the west end, each topped by a tooled ashlar relieving arch. The remaining windows, including those to the chancel, feature cusped tracery with hood moulds and carved foliated stops. The tower is lit by lancets with diamond latticed glazing.

The three-stage tower dominates the south elevation facing the road. The lower two stages are square with a string course between floors; the top corners angle to support an octagonal third stage with oversized louvred arrow loop openings. The tower is topped by a weathercock on a pointed pavilion roof with heather-coloured fishscale banding, a second string course, and a frieze decorated with quatrefoil motifs. The tower entrance faces south and comprises a double-leaf gothic diagonally-sheeted varnished pine door with wrought-iron strap hinges, set in a deeply chamfered sandstone surround with rebated colonette jambs (all new stone) and a sandstone threshold. Two irregularly spaced windows flank the tower to either side.

The principal entrance is at the west gable, where a triple lancet sits above a lean-to vestibule. The vestibule is primarily twentieth-century fabric with stone cladding but includes a gabled centrepiece containing an original stone door with plastic repairs and a worn sandstone threshold. The vestibule is lit by small pointed arch windows to either side.

The north elevation contains three windows and is abutted at its left end by a single-storey vestry with a shouldered diagonally-sheeted pine door to the west and a window to the north. The vestry is in turn abutted at its left corner by the side chapel, which is detailed as a house and lit to the east. The east gable is abutted by the chancel, lit by a traceried window to the east and south, with the south window raised beneath its own gable. The north side of the chancel has a single cusped window.

The church sits in a declivity with lawn to the south, enclosed to the road by a modern rubble stone boundary wall with trees to the remaining boundaries. A gravelled perimeter surrounds the building, with a modern church hall to the east. A war memorial in the form of a rock-faced cut stone Celtic cross stands on the south lawn.