Prior to its expansion with a line to Hammersmith, the Circle Line lived up to its name by forming a loop that encircles much of inner London. Running through Chelsea and Kensington, the City of London, Hackney, Islington, the City of Westminster, and now to Hammersmith and Fulham, the Circle Line runs through practically every major Underground and railway station in London. This, of course, shouldn’t be surprising since it was born out of two of the London Underground’s original lines. Punch your Oyster card and join us on a journey down the tunnels of the Circle Line’s history from its earliest days to the present.
As mentioned, the Circle Line actually got its start from two of London’s oldest Tube lines: the Metropolitan Line and the District Line. Then known as the Metropolitan Railway and the District Railway, both lines were in their earliest days when a Parliament select committee recommended an “inner circle” of railway lines that connected the city’s railroad termini. The two separate lines ultimately had a falling out and the prospect of uniting them into a circle wasn’t realized until Parliament intervened in 1884. Each company ran services in a separate direction, with the Metropolitan trains ran “outer rail”, or clockwise, services and the District ran “inner rail”, or anti-clockwise, services.
In 1882, the Metropolitan extended services to a temporary station at Tower Hill that was replaced with a permanent station in 1884. This completed the inner circle and afterward, the Metropolitan Railway began to run all outer rail services by 1908. Meanwhile, the District Railways was running into financial problems and needed to refinance around 1901. It used to opportunity to fully electrify its services and amalgamated with the Underground Electric Railways of London. This caused some issues between the Metropolitan and District railways that were using different electrical systems, a problem that was solved when the Metropolitan converted its stock to be compatible with District’s system.
In 1933, both the Metropolitan and District railways were absorbed into the public London Passenger Transport Board, forming part of the London Underground. The shared loop between the two lines became formally known as the Circle Line in 1936. On the Underground Map, the Circle Line appeared in the same shade of green as other sub-surface lines including the Metropolitan Line, the District Line, and the Hammersmith & City Line. The Circle Line wouldn’t become its own distinct line until 1948 when it was denoted by a black border and didn’t receive its yellow color until 1949.
Between 1959 and 1960, Circle Line trains were increased up to six cars to match those of Hammersmith & City Lines. The Circle Line trains were also integrated with maintenance at the Hammersmith Depot. For decades, Circle Line stock had been hand-me-downs from other lines but finally received their own brand-new trains in 1970. Single-operator trains were proposed as early as 1972 but weren’t actually introduced until 1984. The Circle Line was also yet another Underground line that was partially privatized in 2003 and run by Metronet until the company went into administration in 2007, at which point it reverted back fully to the management of Transport for London.
Moving further into the 21st Century, the Circle Line was one of the Underground railways affected by the July 7, 2005, terrorist bombings when two explosive devices went off around 8:50 AM. The bombs killed 15 people, including the two suicide bombers, and the line remained close until August 8. In 2009, the Circle Line extended to include the Hammersmith & City Line to Fulham, giving it a little branch off of Paddington, turning the circle pattern into a spiral. Most recently, the Circle Line was closed along with the Waterloo & City Line in March 2020 as part of a pandemic lockdown restricting all but non-essential travel. Now back open and ferrying passengers once again, it remains to be seen where the Circle Line will go in the future.