Cushendall Mill, At rear of 25 Mill Street, Cushendall, Co. Antrim, BT44 0RR

Cushendall Mill is an unusually substantial and well-proportioned early 19th-century water-powered corn mill, built into a south-facing slope in the rear yard of No. 25 Mill Street — the former mill house — in Cushendall, County Antrim. It dates from the 1820s and was almost certainly built by Francis Turnly, the local landlord, whose wealth alone would have made possible such a large and well-constructed building. All plant and machinery have long since been removed, but the mill remains identifiable as such through the survival of two internal grain-drying kilns (unusually, most mills of this type retain only one, often in a separate building), a waterwheel pit, and vestiges of the mill races. The wall fabric and roof framing are original and unaltered.

The building is two storeys tall across four bays, aligned approximately east–west along the foot of the slope, with its principal elevation facing south towards the yard. It measures 93 feet by 26 feet 6 inches and stands 19 feet high — dimensions consistent across all historical valuations. The walls are of random rubble sandstone with roughly-squared quoins and an advanced eaves course; vestiges of original whitewash survive. All openings have voussoired sandstone heads, and windows on the front elevation also have sandstone sills. The roof carries replacement natural slate and half-round metal rainwater goods. All doors and windows are modern timber replacements.

The south elevation, facing the yard, is five openings wide. Its far left (west) end is abutted by a later single-storey building. Reading from left to right, the ground floor has a sliding timber door, a 4×4-paned window, a door, and another 4×4-paned window — the two windows having been inserted into former door openings. At first-floor level there is one window directly above each of the five ground-floor openings: two 2/2 sliding sashes, two 8/8 sashes, and one with 4×4 panes. The east gable is largely blank, with a single 8/8 timber sliding sash at first-floor level, complete with stone head and cill. Because the mill is cut into the hillside, the north elevation is only visible at first-floor level. The left (east) half of this wall has no openings. To the centre there is a wide door, and to the right three windows: one 1×1 light (possibly a later insertion) and two 2/2 sashes, both without cills. The remnants of a later cast-iron stove flue project from the wall between the two rightmost windows. The west gable is inaccessible; its apex is clad with slates and at ground-floor level it is abutted by a single-storey roofless lean-to wheelhouse that originally enclosed the waterwheel. The rubble masonry headrace remains visible at the north-west corner of the site.

The mill sits in a yard enclosed to the north and east by a rubble stone wall, accessed from the south via a laneway off Mill Street. To the west, a petrol station occupies the adjacent site, its boundary marked by a rendered wall.

The historical record for this building is exceptionally detailed. The 1832 Ordnance Survey map shows two corn mills in the townland — this one and a second, older mill further upstream on the River Dall. The 1835 Ordnance Survey Memoir describes the Cushendall mill as "an excellent corn mill with a commodious yard," noting that its overshot waterwheel was 16 feet in diameter and 4 feet wide, while the upstream mill was already old and "in very bad order." The 1834 Valuation records the mill as the property of Francis Turnly, local landlord. The quality rating assigned in the 1835 Valuation — graded '1A+', indicating a slated building constructed within the previous 20 to 25 years — suggests the mill would have needed no refurbishment at that date. The Cushendall Conservation Area booklet (1993) records that Turnly purchased the village and its mill in 1813 and refurbished it in 1838, but it is more likely that the mill he purchased in 1813 was the older upstream one, which he subsequently decided to replace with the present, far superior building, probably during the 1820s.

By the time of the 1859 Valuation, the mill was occupied by George Miller and comprised a house, offices, a kiln man's house, the corn mill itself, kilns, and a yard, with a combined rateable value of £35. The valuation records two pairs of millstones — one for shelling and one for grinding — with sufficient waterpower to work both simultaneously. Additional equipment included fans and sifters for processing grain and meal, though no elevators. Two kiln heads (drying floors) were present. The mill was assessed as working 12 hours per day for six months of the year.

A succession of tenants leased the mill in the later 19th and early 20th centuries: Thomas Thompson (1874), Robert Ferguson (1877), Archibald McKillop (1878), Dorothea Turnley (1880), George Millar (1881), John McGregor (1889), Mary McGregor (1903), Sarah McGregor (1905), James Bond (1912), and Anthony O'Connor (1913). The 1912 Valuation notebook — which describes the mill as 200 years old, almost certainly incorrectly — notes it as dilapidated and worked only five or six months each year at 50 to 55 hours per week.

From 1925, the valuation records show a significant change of use: in addition to the corn mill, an electric light station now appears on the site. This was a private venture by Mr O'Connor, operating as the Cushendall Electric Light and Power Company to supply the village with electricity. The company may have begun generating as early as 1923, when turbine manufacturers Messrs Hay-Maryon of Loughborough recorded the installation of a 15 horsepower turbine on a 20-foot fall at Cushendall. The installation of the turbine almost certainly necessitated the removal of the original waterwheel, and corn milling was in all likelihood abandoned at this time, though grain drying may have continued for a period. In 1929, the company applied to the Electricity Commissioners for Northern Ireland to increase the station's output to 20 kilowatts (27 horsepower), which was granted in March of that year. This increase in capacity was most probably achieved by supplementing the turbine with a diesel engine — according to the mill's then-owner — which may have been housed in the single-storey building abutting the south-west corner of the mill. James Finnegan took over the generating operation from O'Connor around 1937, and was in turn taken over by the Electricity Board for Northern Ireland around 1953. That Board, established under the Electricity (Supply) Act (Northern Ireland) 1931 and empowered to acquire existing generating stations, eventually closed the Cushendall undertaking — one of the last rural enterprises it acquired — once the village was connected to the National Grid. The building subsequently reverted to use as a store.