 From the late 18th century numerous large-scale industrialised collieries operated in the southern section of the North East Wales coalfield, alongside hundreds of more traditional small-scale pits belonging to a mining tradition dating back to the Middle Ages.18th century literary visitors included Samuel Johnson, who described Wrexham as "a busy, extensive and well-built town", and Daniel Defoe who noted the role of Wrexham as a "great market for Welch flannel".The artist J. M. W. Turner also visited the town and painted a watercolour of a street scene entitled "Wrexham, Denbighshire" dated 1792–3.