Lead had been mined in Derbyshire on a commercial scale since at least 1300, but the industry was hampered by poor transport links. The pigs of lead were carried by pack horses to Bawtry, where there were wharves on the River Idle. Small boats carried them to the River Trent, where the cargo was transferred to larger vessels for onward distribution. There was no proper system of road maintenance, and so the use of carts and wagons for the over-land journey was not possible. The River Idle was also unreliable, being affected by floods and droughts, but there were no alternatives, and the industry flourished despite the difficulties. The Derwent Navigation was authorised in 1719, running from Derby to the River Trent, but it was less reliable than the Idle, and so did not seriously affect trade through Bawtry. The London Lead Company, one of the main traders, together with others involved in lead and coal mining, looked for possible solutions, and were joined in this by several prominent landowners.