River Tillingbourne

The River Tillingbourne (also known as the Tilling Bourne) runs along the south side of the North Downs and joins the River Wey at Shalford. Its source is a mile south of Tilling Springs to the north of Leith Hill at grid reference TQ143437 and it runs through Friday Street, Abinger Hammer, Gomshall, Shere, Albury, Chilworth and Shalford. The source is a semi-natural uninhabited area. The catchment is situated on sandstone which has a low rate of weathering. The Tillingbourne is 24 km (15 mi) in length.

The Tillingbourne initially flows northward for 4 km (2.5 mi) down the northern slopes of Leith Hill over a series of weirs and cascades, before turning west to run for 14 km (8.7 mi) through Abinger Hammer and Chilworth towards the River Wey at Shalford. The river is classified as a subsequent stream, since its course is determined by the direction of the stratum of softer rock for the majority of its length.

The river has four principal tributaries: the Friday Street stream joins at Wotton House; the Holmbury St Mary stream joins at Abinger Hammer; the Sherbourne Brook drains the Silent Pool and Sherbourne Pond and the Law Brook joins near Postford.

From the 17th to the mid 20th centuries the Tillingbourne valley was a major industrial area due to its closeness to London and the ease of transport via the Wey and the Thames. The river was used to power a relatively large number of mills in the area. Some 24 mill sites have been identified along the course of the river, used for such diverse industries as gunpowder, paper making for bank-notes, iron-working, wire-making, fulling, tanning and pumping water, as well as the more conventional flour, grist and malt milling. Some of the earliest gunpowder mills were those set up in 1626 by The East India Company at Chilworth.

John Evelyn wrote in his diary in 1676:

I do not remember to have seen such Variety of Mills and Works upon so narrow a Brook, and in so little a Compass, there being Mills for Corn, Cloth, Brass, Iron, Powder etc.

Not every one was so impressed, William Cobbett wrote:

This valley, which seems to have been created by bountiful providence, as one of the choicest retreats of man, which seems formed for a scene of innocence and happiness, has been, by ungrateful man, so perverted as to make it instrumental in effecting two of the most damnable of purposes; in carrying into execution two of the most damnable inventions that ever sprang from the minds of man under the influence of the devil! Namely, the making of gunpowder and of banknotes!