The British invented them for the world, and they have been described as 'the lungs of the city - historian Dan Cruickshank reveals the history of our public parks. Cruickshank travels the country to discover the evolution of the nation's urban public parks, a story of class, civic pride, changing fashions in sport and recreation which helps re-evaluate the amazing assets they are. From their civic heyday in the 19th century to the neglect of the 1980s and their resurgence today, the documentary is a fascinating and entertaining history of an often-overlooked great British invention.