You can't have missed that it's London Underground's 150th anniversary this week – Google's even dedicated its home page doodle to the birthday of the oldest subway system in the world. Alongside this, the network has given us images of a series of posters that have been displayed at its stations across its history.
The posters stretch from 1923-2003 and feature the work of artists including Alfred Leete, Alfred France and Paul Catherall. LU notes that the Tube network carries 1,107 million passengers each year to 270 stations. To mark 150 years of operation, London Underground, working in partnership with the London Transport Museum, will hold a range of events and activities including the recreation of the Tube's first journey, special events at disused stations and the publication of a series of books.