The valley is deeply incised into Tunbridge Wells red sandstone, with a base of alluvium on Wadhurst clay.

This formed Bewl Water, a 30-metre-deep storage reservoir (98 ft), with a surface area of 308 hectares (760 acres).

When Bewl Water was built, the fourteenth century Mill House was dismantled and re-erected at Three Legged Cross, Wadhurst.

it drove a cast iron pit wheel 10 feet 8 inches (3.25 m) diameter with 112 wooden cogs.

It was in the Culpeper family in the sixteenth century, Thomas Collepepper holding lands in Chingley in fief from Henry VIII in 1544.

There is evidence that Chingley Forge was a hammer mill at some time, possibly as early as the first half of the thirteenth century.

[4][5][6][7][8][9][10] When the site was excavated in 1970, the remains of an overshot waterwheel 8 feet (2.44 m) diameter and 1 foot (0.30 m) wide were found.