Richard Arkwright and his partners established a mill in Cromford in 1771 and without delay set about perfecting the machinery and production methods for water - powered cotton spinning. The first mill was modest in size, but in 1776 a second and very much larger mill was established using the same water supply. Soon after, the mill site expanded again and massive engineering work was undertaken, to create the system of ponds and underground culverts which maintained Arkwright's increasing need for water to drive his machinery. Cromford mill is now a world heritage site. Restoration of the old mill has been carried out by the Arkwright society which purchased the site in 1979.