The Victoria line is part of the London Underground network. It is a deep-level underground metro line that runs from Brixton in south London to Walthamstow Central in the north-east. It started running in 1968. On the Tube map it is shown with a light blue color. It is the fourth busiest line on the London Underground network. It is the only line on the Underground, other than the two-stop Waterloo & City line, which is completely underground. The only section of track to come above ground is the route to the depot from Seven Sisters to Northumberland Park.