History of the London Underground services reached Richmond, Ealing, Hounslow and Wimbledon. As part of the project that completed the Circle line in October 1884, the District began to serve Whitechapel. As a result of the expansion, by 1898, 550 trains operated daily. Services began running to Upminster in 1902, after a link to the London, Tilbury & Southend Railway had been built. In 1869, a passage was dug through the London Clay under the Thames from Great Tower Hill to Pickle Herring Stairs near Vine Street (now Vine Lane). A circular tunnel was dug , using a wrought iron shield, a method that had
Central line (London Underground) and realigned and the stations lengthened, but it proved impossible to modify Wood Lane station to take 8-car trains and a new station at White City was authorised in 1938. The line was converted to the London Underground four-rail electrification system in 1940. The positive outer rail is higher than on other lines, because even after reconstruction work the tunnels are slightly smaller. Most of the tunnels for the extensions to the east of London had been built by 1940, but work slowed due to the outbreak of the Second World War until eventually suspended in June. The unused tunnels