Rumour has it that the Bakerloo line originated from the desire of a few London businessmen to get to and from Lord's Cricket Ground as quickly as possible. Nevertheless, when the line opened between Baker Street and Lambeth North on 10th March 1906, over 36 000 passengers were carried despite the fact that the cricket season had yet to start.
Originally known as the Baker Street and Waterloo Railway, the name was officially changed in July 1906 to the Bakerloo Railway reflecting the nickname coined by the Evening News. Elephant & Castle station opened in August 1906.
The Bakerloo line was extended from Baker Street to Queen's Park in 1915 and further north over existing suburban railway tracks to Watford Junction by 1917. In 1939, a new-tunnelled section was built from Baker Street to Finchley Road, which allowed Bakerloo trains to take over the Metropolitan line's service, originally started in 1932, to Stanmore.
Until the opening of the Jubilee line in 1979, the Bakerloo operated both Stanmore and Watford Junction services. The building of the Jubilee line from Charing Cross to Baker Street, and its connection to the Stanmore branch of the Bakerloo Line, left the Bakerloo again with only its Watford Junction branch.
In 1982, the service beyond Queen's Park to Watford Junction, by then only four peak period trains, was withdrawn. Queen's Park again became the northern terminus, although there were some journeys to and from the new Stonebridge Park depot. In 1984 some peak period journeys were extended to Harrow & Wealdstone, and the present all-day, daily, service to Harrow & Wealdstone began in May 1989, and has been regularly enhanced in recent years.