The Northern Line is a major underground railway line in London, part of the London Underground network. It runs from north to south, connecting areas like High Barnet, Mill Hill East, Kennington, and Morden. The line is known for its distinctive black color on maps and serves both residential and commercial districts. The Northern Line has 50 stations and is divided into two branches: the City Branch and the Charing Cross Branch. It is one of the busiest lines in the network, providing essential transport for commuters and tourists alike, facilitating access to key locations such as London Bridge and Leicester Square.