1. I discuss the development of turnpikes in The Making of the British Landscape (Penguin Books, London, 2011), pp. 451–6; see also C. C. Taylor, The Cambridge Landscape (Hodder and Stoughton, London, 1973), pp. 227–8.
2. For example: www.ourownhistory.com/walk_ermine_street.htm.
3. N. Pevsner, The Buildings of England. Cambridgeshire (Penguin Books, Harmondsworth, 1954), p. 246.