There are 170 watermills and dams shown on this map, dating from the 1200’s to the 1930’s all using water power to drive tilt hammers, blowers for forgers, grinding wheels for sharpening knifes and scythes as well for the milling of corn and other grains. On the Sheffield side each mill has a brief chapter of the places history taken from the now out of print book ‘The Water-Mills of Sheffield’ by W.T. Miller, 2nd Issue, published in 1947 plus some additional material from ‘Water Power of the Sheffield Rivers’, 2nd edition, Christine Ball (ed.) published in 2006. The mills on the Rotherham and North Derbyshire sides have their sources linked in the text.