James Roberson follows the course of the River Derwent as it winds its way through Derbyshire
Derbyshire's longest river, the Derwent, starts as a series of small streams which drain from the large peat mass known as Bleaklow, though its commonly accepted source is at Swain's Greave on Howden Moor.
From this point it has 66 miles to go before it joins the Trent just south of Derby.
After only a few miles, the burgeoning river meets its first major landmarks - three consecutive reservoirs: Howden, Derwent and Ladybower, all built in the first half of the 20th Century and at the expense of two villages, Ashopton and Derwent, which were covered by the water.
THE RIVER DERWENT
The name "Derwent" is Celtic and means "a valley thick with oaks".
The river was made navigable under an Act of 1720 and opened for the 10 miles up to Derby
The entire river is within the county of Derbyshire
There are four other Derwent rivers - in Tyne and Weir, Yorkshire, Cumbria and Tasmania
The similarity between the Upper Derwent Valley and Germany's Ruhr Valley made the Derbyshire watercourse an ideal place for target practise for Barnes Wallis's 'bouncing bombs' in 1943 and was used by Lancaster bombers from the 617 Dambusters Squadron.
Soon, the river reaches Bamford, Hathersage, Grindleford and Froggatt. Then Calver, with its 18th Century Bridge and the former Calver Mill, built using the power of the river. It was once a thriving cotton mill but most famous perhaps as Colditz Castle in the BBC television series of 1972-1974.
Next is Baslow and then the magnificent grounds of Chatsworth and on to Rowsley, where it is joined by the River Wye.
Darley Dale and Matlock follow - then on to Matlock Bath as it cuts its way through the limestone creating the spectacular, steep cliffs on its eastern bank.
Derby's Silk Mill is one of many in the Derwent Valley Mills world heritage site
At this point the river reaches the Derwent Valley Mills World Heritage Site, a 16-mile stretch of river containing a series of historic mill complexes which formed some of the world's first modern factories.
Within the World Heritage Site are Masson and Cromford Mills, Strutts Mill, John Smedley's Mill and Derby's Silk Mill.
After Derby, the river heads through Spondon, Borrowash and Draycott before reaching its confluence with the River Trent at Derwent Mouth near Shardlow.
Its waters ultimately flow into the North Sea via the Humber Estuary.