The Hammersmith & City line is a London Underground line that runs between Hammersmith in west London and in east London. Coloured pink on the Tube map, it serves 29 stations over . Between and it skirts the City of London, the capital's financial heart, hence the line's name. Its tunnels are just below the surface and are a similar size to those on British main lines. Most of the track and all stations are shared with either the District, Circle or Metropolitan lines, the other parts of London Underground's sub-surface railway, and over 114 million passenger journeys are made each year on the Hammersmith & City and Circle lines.