The River Medway and its tributaries and sub-tributaries have been used for more than 1,150 years as a source of power. There are over two hundred sites where the use of water power is known. Many different processes were performed by the use of water power:- corn milling, fulling, paper making, iron smelting, pumping water, making gunpowder, vegetable-oil extraction, and electricity generation. Today, there is just one watermill working for trade. Those that remain have mostly been converted. Such conversions include a garage, dwellings, restaurants, museums and a wedding venue. Some watermills are mere derelict shells, lower walls or lesser remains. Of the majority, there is nothing to be seen. A large number of tributaries feed into the River Medway. The tributaries that powered watermills will be described in the order that they feed in. The mills are described in order from source to mouth. Left bank and right bank are referred to as though the reader is facing downstream. This article deals with the watermills on the tributaries that feed in below Yalding. Wateringbury Stream. The Wateringbury Stream enters the Medway from the left at Wateringbury. A site close to the source of the Wateringbury Stream shows some characteristic signs of previous use of waterpower. Swanton, Mereworth A large pond high in the Swanton valley may indicate the site of an old furnace mill. The head available being sufficient to power a large overshot waterwheel. Mereworth Mill. The Domesday Book records two mills, value 10/-, at Marovrde (Mereworth). The site of the last mill now lies in the grounds of Mereworth Castle. In 1460, the mill was held by Thomas Hunte. In 1521 it was a fulling mill, belonging to Sir Thomas Nevyle. In 1772 James Pound was the occupant, followed by his widow in March 1780 and John Pound in September 1780. He was at the mill until October 1791. Thomas Edmead was at the mill from 1792-1827. The mill was purchased by Viscount Falmouth c.1856. The mill was demolished by 1907 and the site is today marked by a waterfall at the eastern end of the lakes in the grounds of Mereworth Castle. The head would have been some or , suggesting a high breast shot or overshot waterwheel., Mill at Wateringbury The Domesday Book records three mills at Otringeberge (Wateringbury). Two mills were held by Ralf, son of Turald and valued at 3/-, a third was