Mobil gradually expanded its operation into fuels retailing as well, and opened its first UK service stations in the early 1950s, after the wartime POOL monopoly was disbanded. Mobil grew to become the seventh largest brand of petrol in Britain, supplying 1,990 outlets in 1965, and claimed in the mid-1960s to be the first company to operate 100 self-service stations. As well as its downstream interests, Mobil was active in the North Sea and operated an oil refinery in Coryton (opened in 1953), on the Thames estuary.