In the mid 20th century Cwm-bran was a small village whose development was based around the coal, iron and tin-plate industries of the area. 

Cwmbran was then designated for one of fourteen `Mark 1' New Towns designated around the UK under the 1946 New Towns Act and the only one to be designated in Wales. Cwmbran New Town began life on 4th November 1949 when an area of 3,160 acres of land around the existing villages of Cwm-bran, Pontnewydd and Croes-y-ceiliog was designated by the Minister of Town and Country Planning as the site of a New Town for a population on 35,000 people. 2,550 acres were in the Urban District of Cwmbran, the remaining 610 acres in the Rural District of Pontypool and the existing population was c.13,000. The land consisted of a mixture of existing villages, abandoned clay pits and colliery workings and agricultural land. The Afon Lwyd ran through the area, as did the disused Monmouth and Breconshire Canal. Two railway lines were already in existence; the Hereford - Newport main line and the Monmouthshire Eastern valleys line. Outside of the designated area, a one mile Green Belt was imposed as a boundary to the development.

On November 24th of the same year the Cwmbran Development Corporation was set up charged with the duty of developing the town and providing housing with proper social and commercial facilities. These facilities were to serve the workers of the large amount of industry already located in the area, and in this sense Cwmbran was different to many other new towns that were aimed at dispersing population from crowed inner cities. There were 20 existing factories in the designated area employing over 6000 workers, and a number of major industries nearby including the British Nylon Spinners factory, the Panteg steelworks and the Royal Ordnance Factory at Glascoed.

In March 1950 the firm of Minoprio & Spencely & P w Macfarlane were appointed as planning consultants, Mr Minoprio having recently completely the masterplan of Crawley. The Chief Architect was J C P West and Chief Engineer was Lt-Col A Borlane. Chairman of the Corporation Board was T H Huxley Turner.

In March 1951 `A Plan prepared for The Cwmbran Development Corporation? was submitted outlining the plan for seven residential areas, each with its own neighbourhood centre linked together by a road and new bridges over the existing railway line, canal and river together with a new town centre; Pontnewydd, Greenmeadow, St Dials, Coedeva, Oakfield, Croes-y-ceiliog North & Croes-y-ceiliog South (renamed Llanyravon) and the town centre. Most of the housing was on higher ground while the town centre, industrial, service industry and recreational areas were on the plain in the centre of the valley. Groups of important public buildings were located at the north and south ends of the main shopping street, while a major educational centre comprising of four secondary schools was designated at Croes-y-ceiliog.

In June 1961 the Minister for housing and Local government proposed that the population within the designated area should be increased to 55,000and in 1962 an expansion plan was drawn up. This involved the creation of six new smaller neighbourhoods: Upper Cwmbran, Thornhill, Fairwater, Hollybush/Two Locks, Llanyravon and Southville. It also proposed a new layout for the town centre which took place between 1963 and 1977. By 1965 a total of 5,300 houses had been built and the population stood at 35,500.

In 1978 the town still hadn't reached the population target of 55,000 and looked to increase the size of the designated area of the New Town in order to achieve this. Henllys, an area of 142 hectares, was added to the development plan with a proposed 1,900 houses, two primary school and shops.

The Cwmbran Development Corporation came to an end in the mid-1980s. The town centre was sold to Ladbrokes in 1985 and 4,083 houses were also sold, 3,068 under the 1980 `Right to Buy' scheme. In 1986 the remainder of the houses, the recreational and open spaces and the neighbourhood centres were transferred to Torfaen Borough Council. The Henllys expansion area was sold to private developers and Land Authority Wales for development and 250 employment units were sold to the private sector with the remainder sold to the Welsh Development Agency.

S Fielding, RCAHMW, April 2018