Light House, Mew Island, Donaghadee, Co. Down

Mew Island Lighthouse is a substantial offshore lighthouse complex built between 1882 and 1884, situated on the rocky northern coastline of Mew Island — a relatively small piece of land measuring less than half a mile at its greatest length, lying three miles off the north-east coast of County Down and four miles north of Donaghadee. The complex was designed by William Douglass, engineer to the Commissioners of Irish Lights, and constructed by Messrs. Thomas S. Dixon & Co. of Belfast, who commenced on site in July 1882. It came into official operation on 1 November 1884.

The complex is dominated by a 37-metre-high lighthouse tower, reputedly the tallest on the island of Ireland, and is considered a testament to the ambition of the Commissioners of Irish Lights and the skill of the 19th-century engineers and workmen who built it. All principal structures are of rubble masonry quarried on the island, with granite dressings brought from Newry. Their distinctive design represents a variant of the building typology adopted by Irish Lights for both onshore and offshore stations.

The complex is laid out roughly on an east-west axis and follows a broadly symmetrical H-shaped plan. The lighthouse stands slightly east of centre, linked via narrow corridors to the lighthouse keeper's quarters to the west and the fog horn engine house to the east. A former gasworks compound lies at the western end of the site, and a small yard and shed occupy the space between the keeper's quarters and the compound. All principal structures are enclosed by original boundary walls.

The lighthouse tower is circular in plan and tapers from a base external diameter of 33 feet — with walls 6 feet thick at ground level reducing to 4 feet 6 inches at the top — up to its full height of 37 metres, capped by a glazed lantern. The tower is finished in painted render, stuccoed in Portland cement painted black with a white band. Small flat-headed windows are set at each of four levels to both the north and south faces, with additional windows to the east and west at the uppermost level; these are filled with timber sash frames, some one-pane over one, others two over two. The linking corridors abut the tower at ground level to the east and west, with access possible only via the western link from the keeper's quarters. The large multi-sided lantern is entirely glazed except for its lowest section, which is clad in painted iron panels with simple geometric decoration. The lantern has a sloping concave roof rising to a central cupola, and is painted white. A walkway with iron railings encircles the lantern at its lower level.

The lighthouse keeper's quarters are contained within a small, plain single-storey gabled building, rectangular in plan. To the west is a small off-centre flat-roofed porch; to the east are a gabled linking corridor and a flat-roofed projection added after 1964. The walls are finished in painted render, the roof is slated with rendered parapets, a bracketed eaves and two symmetrically arranged rendered chimney stacks. Entrances to the north and south faces of the porch each consist of a plain sheeted door. To the west face of the porch is a small flat-headed window with a timber sash frame (two over two). To the left of the porch are two flat-arched windows with timber sash frames (six over six), with one more to the right. The east elevation has a similar window to the left of the projection and corridor, with two more to the right. The projection has three flat-headed windows to its south elevation filled with PVC frames, one of which is largely louvred. To the north elevation of the link there is a timber-sheeted door to the left and a small timber sash window (two over two) to the right.

To the west side of the keeper's quarters is a small yard enclosed by tall rendered walls to the north and south, with a single-storey shed to the west. The shed is finished in painted render to its north, south and east elevations; its west façade, which forms most of the east wall of the former gasworks compound, is of rubble stone. The slated roof is of single pitch with rendered parapets. To the east elevation there are three unevenly spaced timber-sheeted doors and two windows with timber sash frames — the left one two over two, the right one six over six.

The fog horn engine house at the eastern end of the complex is broadly similar in character to the keeper's quarters, being roughly rectangular in plan with a slated gabled roof and walls finished in painted render. It is abutted to the west by the link corridor to the lighthouse, to the north by the look-out tower, and to the south by a slightly lower gabled projection with brick quoins. To the west elevation, to the right of the link, there is a large flat-headed doorway with a timber-sheeted double door; to the right of this, on the south projection, a slightly smaller segmental-headed doorway with a brick lintel and a similar door. The north gable has a flat-headed window with a timber sash frame (six over six), with a similar window to the south gable of the projection and two more to the east elevation.

Attached to the north face of the engine house is a two- to three-level octagonal look-out tower dating from around 1970, with an oversailing control room similar to those seen at small aerodromes.

At the western end of the complex is the former gasworks compound: a large, irregularly shaped yard enclosed by a tall rubble stone wall with a castellated rendered coping and brick quoins. On the west side of the yard stands a single-storey gabled building slightly larger than the keeper's quarters, with a long lean-to to the west and a lower gabled projection to the north. The front and south elevations are finished in painted render; the remaining elevations are of rubble stone with brick dressings to the openings. The slated roof has a small metal flèche to the south of centre of the ridge. The front elevation has three tall windows with timber frames and hopper openings (likely replacements) and two doorways with timber-sheeted doors and large two-pane fanlights. To the east elevation of the northern projection is a small flat-roofed porch with a doorway and matching door. The south elevation of the main building has two windows matching those on the front elevation and a further doorway to the left, which is actually on the side of the lean-to section. To the west side of the lean-to are two brick-dressed segmental-headed windows filled with glass blocks. To the left of the lean-to, on the main building, are two more windows set at differing levels: the left one matches the front windows, while the right one has been adapted to allow access for flues from machinery inside. A small window on the north gable of the projection has been blocked up.

To the south side of the gasworks compound is a single-storey flat-roofed shed added after 1964, rendered and with three doorways to its north elevation — two pedestrian doorways with doors and a larger but lower doorway to the right without a door. A smaller similar shed occupies the north-east corner of the yard, with a pedestrian doorway to its south face. To the west of the larger shed is a vehicle entrance with stone piers and a modern replacement metal gate. Within the yard itself are two (possibly three) large circular gasometer pits; the remainder of the yard has largely been reclaimed by grass.

To the south of the main complex is a helicopter landing pad. Further south again are several small single-storey buildings of one to two rooms with whitewashed facades and gabled roofs, most likely the rudimentary dwellings built to house the workforce during construction, as referenced in contemporary newspaper reports. A report in the Northern Whig of 24 July 1883 records that "upwards of fifty hands were employed" on an island "entirely destitute of shelter", and that the contractors were forced to erect houses for the workmen' accommodation. It is probable that further such structures were originally built and cleared away once construction was complete.

The complex has undergone several documented changes since it was built. In 1895, an additional fog horn was ordered due to the inadequacy of the existing siren. In 1928, a new optic — originally the world's first and largest hyper-radial Fresnel lighthouse lens, installed at Tory Island lighthouse in 1887 — was adapted and fitted at Mew Island. Also in 1928, the gas-making plant, the last still operating around the Irish coast, was discontinued and paraffin vapour burners substituted for coal gas. The apparatus was converted to electricity in 1969. The post-1964 flat-roofed extension to the rear of the keeper's quarters and the larger modern building to the north of the workers' dwellings are likely to have been built in connection with the look-out tower, which also dates from after 1964. The keepers were permanently withdrawn from the station on 29 March 1996 following conversion to automatic operation. In 2014, the optic was removed and the lighthouse converted to solar power. The optic was subsequently housed in a purpose-built structure on the Titanic walkway in Belfast, opening in 2018.

The background to the complex's construction is well documented. In 1881, following many years of representations from ship-owners and others, the Board of Trade sanctioned a new gas-lit lighthouse on Mew Island to replace the long-established, by then oil-lit, lighthouse on neighbouring Lighthouse Island, which was considered inadequate. The Copeland Islands had long proved dangerous to navigation: the earlier light — originally coal-fired, latterly using twenty-seven paraffin-oil lamps in three rows of nine — though visible from sixteen miles, had not prevented repeated shipwrecks in foggy conditions, some involving loss of life. After the loss of the steamer Sea King, when three vessels were simultaneously aground, a fog bell was installed, but this too proved insufficient. The design was prepared by William Douglass, engineer to the Commissioners of Irish Lights, tender notices for the various aspects of the work — builders' work, gas apparatus, lanterns, lenses and fog signal — were advertised in January 1882, and construction ran through to 1884. The gas apparatus was supplied by Messrs. Edmondson of Dublin, who also supplied the lantern, the latter having been exhibited at the Dublin Exhibition the previous year and frequently illuminated outside the Rotunda. The site was chosen approximately one hundred yards from where the steamer Electric had stranded on 30 June 1883. Work was carried out under the direction of Mr F. B. Foote, C.E., Engineer to the Irish Lights Commissioners. Two gasometers were provided, each with a tank 25 feet in diameter by 15 feet in depth. The first-class dioptric lens produced an uncoloured fixed light intended to be visible for thirty miles, with the keeper able to increase the lighting power threefold in hazy weather. The fog siren, driven by a gas engine, was designed to be audible at twenty miles and expected to be heard as far away as Portpatrick. Upon completion, the old lighthouse tower on Lighthouse Island was retained without its lantern as a daymark.

The Mew Island complex has group value with the other nineteen listed lighthouses and navigational aids on the Northern Irish coast.