[4] The solid geology of Baptist Mills comprises Triassic Redcliffe Sandstone, which is overlain by superficial deposits of Quaternary alluvium in the floodplain of the Horfield Brook and the River Frome.
A grist (flour) mill is recorded in this area in a document written in 1470, and again in 1610, when they are marked on Chester and Master's Map of Kingswood.
In 1706, further partners were admitted, the business becoming an early unincorporated joint stock company with a capital of £8000.
While there, Darby recruited skilled 'Dutchmen' to operate a brass battery with trip hammers.
[1] The following suburbs are in the same urban area, but lie in South Gloucestershire or North Somerset: