Old Transco gas supply infrastructure, national grid pipes and valves, Bradshaw lane, Thelwall, South Warrington, Cheshire, England, UK, WA4 2NL

The United Kingdom's National Transmission System (NTS) is the network of gas pipelines that supply gas to about forty power stations and large industrial users from natural gas terminals situated on the coast, and to gas distribution companies that supply commercial and domestic users. It covers Great Britain, i.e. England, Wales and Scotland The system originated in the construction during 1962–3 of the 200-mile (320 km) high-pressure methane pipeline from Canvey Island (on the Essex coast) to Leeds. Imported liquified natural gas (LNG) from Algeria was turned into gas at the Canvey terminal and supplied to the pipeline, providing eight of the twelve area gas boards with access to natural gas. The gas was initially used to manufacture town gas, either as a feedstock in gas reforming processes or to enrich lean gases such as that produced by the Lurgi coal gasification process. The pipeline was 18-inch (460 mm) in diameter and operated at 1, 000 pounds per square inch (69 bar). The pipeline had 150 miles (240 km) of spur lines, supplying gas to area boards To exploit the availability of natural gas and to provide for more widespread distribution, construction began of a major new transmission network which became the National Transmission System