High Quality Content by WIKIPEDIA articles! The North London Line is a railway line which passes through the inner suburbs of north London, England. Its route is a rough semicircle from the south west to the north east, avoiding central London. The line is owned and maintained by Network Rail. Although much of it originated as part of the North London Railway, the current route is the result of a series of amalgamations, closures and re-openings; and has a mixed third-rail and overhead electrical power supply. It is an important freight route and is used by the Richmond to Stratford service of the London Overground, as part of the National Rail network. Also between Richmond and Gunnersbury, London Underground`s District line shares tracks with London Overground services, although this part is also owned and maintained by Network Rail.