River Idle

The River Idle is a river in Nottinghamshire, England. Its source is the confluence of the River Maun and River Meden, near Markham Moor. From there, it flows north through Retford and Bawtry before entering the River Trent at Stockwith near Misterton. The county boundary with South Yorkshire follows the river for a short distance near Bawtry, and the border with Lincolnshire does the same at Idle Stop. Originally, it flowed northwards from Idle Stop to meet the River Don on Hatfield Chase, but was diverted eastwards by drainage engineers in 1628.

Most of the land surrounding the river is a broad flood plain. Between Retford and Bawtry, the floodplain is partly occupied by a number of sand and gravel pits, where exhausted forming public lakes for fishing, while beyond Bawtry, the river is constrained by high flood banks, to allow the low-lying areas to be drained for agriculture. Its main tributaries are the River Poulter and the River Ryton.

The river is navigable to Bawtry, although navigation rights were removed in 1972. It is also important for conservation, with the Idle Washlands and some of the sand and gravel pits of the Idle Valley being designated Sites of Special Scientific Interest.