St Columbanus, 68 Groomsport Road, Ballyholme, Bangor, Co Down, BT20 5NE

St Columbanus is a freestanding double-height Romanesque church built in 1939 to designs by architect Robert Sharpe Hill of Belfast. The building is located on an elevated site on Groomsport Road in the Ballyholme area of Bangor, in suburban surroundings.

The church has an irregular plan form comprising a nave, single side-aisle, apsidal chancel and tower. It is constructed in squared-rubble rock-face buff-coloured stone with red sandstone banding and a basalt plinth. The roof is pitched Westmoreland green slate with clay ridge tiles, corbelled stone eaves, and cast-iron ogee-moulded gutter with circular downpipes. Windows are leaded stained glass embedded into timber frames set within arched openings. The principal entrance consists of double-leaf arched varnished timber doors, each of six flat panels arranged vertically.

The north elevation, which faces the road, is asymmetrically arranged with a gabled single-storey porch on the right, accessed by paved steps with mild steel handrails. Two windows serve the aisle, with a flush gabled transept to the left and a centred window with quatrefoil opening above. The east elevation is gable-ended with an apex cross, abutted by a single-storey apse with an adjoining double-height squat square tower to the right. The tower has a rear entrance porch on its east face and a small window mid-way with a louvred opening above, rising to a parapet with pyramidal slated roof. The south elevation features three windows to the nave and a projecting gabled transept with a central window and quatrefoil opening. The west elevation is gable-ended with a lean-to gable adjoining to the right, a single-storey lateral buttress left of centre, and two ground-floor windows with a large central rose window above.

The church was built using stone from Roxborough Castle in County Tyrone. The builder was Sutherland, Montgomery & Co., and the construction cost was £7,500. The foundation stone was laid in 1939 and the church was consecrated in 1940. The dedication to St Columbanus reflects the fact that Columbanus was the most celebrated missionary saint to be educated at Bangor Abbey.

The church began as a chapel-of-ease for parishioners in the Ballyholme area during the 1920s and 1930s, when the district underwent sustained growth. The Select Vestry of Bangor Parish purchased the site in 1923 and built a church hall in 1927, which served until the new church was constructed. The church initially served as a daughter of Bangor Parish but achieved parochial status in 1955, becoming the parish church of Ballyholme.

The bell, cast in 1670, was transferred from Saint Patrick's Cathedral, Dublin. A Conacher organ was installed in 1949. A church hall built in 1957 to designs by W.D.R. and R.T. Taggart has since been replaced by a Parish Centre, which opened in 2006.

The church grounds are small with light vegetation and are bounded by modern steel railings and gates fixed to original double rounded coping stones and piers. To the rear is a modern church hall and offices with associated car parking. To the east is a vacant modern two-storey commercial premises; to the west are three-storey modern apartments. North of the site are two-storey detached and semi-detached Edwardian houses.