Haig Colliery was a coal mine in Whitehaven, Cumbria, in north-west England. The mine was in operation for almost 70 years and produced anthracitic coal which is most useful for coking coal. Situated on the coast, the underground workings of the mine spread westwards out under the Irish Sea and mining was undertaken at over 4 miles (6.4 km) out underneath the sea bed.
The mine was sunk in 1914 with production not starting until 1916, and full production not starting until 1925. The mine was named after Douglas Haig, the First World War commander. This followed a typical pattern of naming pits after famous figures of the day in Cumbria (Ladysmith after the battle and Wellington after the former Prime Minister).
The colliery was connected to Wellington Colliery in 1922 and the two mines worked in conjunction with each other until Wellington closed in 1932. Initially Haig was operated by the Bord and pillar method, with Longwall mining taking over from the late 1930s.
The mine’s first shaft was known as No. 4 as three other shafts had already been dug in the same area belonging to other mines located closer to Whitehaven Harbour. Shaft No. 4 was 1,270 feet (387 m) deep and 19 feet (5.8 m) in diameter. No. 5 shaft was constructed at the same time, but the winding gear and steam engine were not installed until 1920-1921 and its shaft was slightly wider at 22.2 feet (6.77 m) in diameter. The engines powering both shafts were built by Bever Dorling of Bradford. Initially, No. 4 shaft was used to transport everything in and out of the mine, but when No. 5 shaft was fitted out, all coal came via that shaft with No. 4 being used for man-riding only. The mine extended out across the Saltom Bay area of the Irish Sea for 4 miles (6.4 km).
In the almost 70 years that Haig was in production, it brought 48,000,000 tonnes (47,000,000 long tons; 53,000,000 short tons) of coal to the surface. The winders were limited to 6 tonnes (5.9 long tons; 6.6 short tons) capacity, which meant that on average, the mine only produced 700,000 tonnes (690,000 long tons; 770,000 short tons) per annum.