London Underground is renowned for its poster archive and the Tube has become 'London's longest art gallery'. Historically these eye-catching posters enticed prospective travellers indirectly by focusing on the destination rather than the mode of travel and as the Underground expanded so did its potential destinations - from the inner city, through suburbia and beyond to the rolling countryside. The London Underground Poster Diary 2012 focuses on posters from the 1930s - these are bolder, brighter and more adventurous than those of the 1920s and their imagery varies from traditional naturalistic scenes to more radical geometric and even abstract interpretations of a subject. As well as Tube facts and trivia, the London Underground Poster Diary 2012 features posters by designers including Dora M. Batty, Charles Pears, Herry Perry, Zero and Man Ray.