[1] Less than 4 miles (7 km) in length,[2] its waters are very clear due to the limestone rock over which it flows, and its width has been enhanced by a number of weirs which also encourage white-throated dippers to breed in the ponds created.

The river is owned and managed by the Haddon Estate and is home to brown trout and white-clawed crayfish.

It is called Rowlow Brook, and is ephemeral, with the point at which water appears in the channel varying with the amount of rainfall.

[5] It passes under the road at Dale End, and then back again to enter Fishpond Wood, where there is a large pond, before it curves around to the north.

It dates from the Bronze Age, and is semi-circular in shape, due to agricultural activity destroying some of the original circular earthworks.

[7] The river is crossed by the road to Lowfields Farm and continues northwards to reach Middleton-by-Youlgreave, where it enters another wooded section.

The first was at Gooseholme, an area of flat pasture land where the medieval residents of Middleton-by-Youlgreave grazed flocks of geese.

[22] Dates for the deveopments at this site are tentative, since Gregory suggests that the building was first used for making tape, then pill boxes, followed by bobbins, with production ceasing by the 1850s.

It was subsequently rebuilt, as the death of the miller William Fletcher, who fell into the machinery, resulted in an inquest being held in 1807.

The lower four dams were created to manage trout within the river for fly fishing, rather than water supplies to the mill.

[28] Between Gooseholme and Holywell Lane at Youlgreave, the river bed descends by over 82 feet (25 m), and the weirs account for about half of that drop.

Prior to the construction of the dams, this would have resulted in a narrow and fast-flowing river, rather than the wide and slow-moving ponds that characterise the dale.

[29] The river was subsequently treated like a fish farm, with stocks of trout delivered by lorry each spring, and little thought given to whether conditions were suitable for them to survive the winters.

This has involved raising the boards on some of the weirs, so that levels in the ponds are lowered, and the river cuts a more natural path through the landscape.

[33] The Wild Trout Trust suggested that the best options for improving the ecology of the river would be to remove the dams, but also recognised that this would be contentious.

Other improvements could be made by the use of large woody debris within the channel, and the addition of extra gravel at suitable locations for spawning.

There are several components that are used to determine this, including biological status, which looks at the quantity and varieties of invertebrates, angiosperms and fish.

Like most rivers in the UK, the chemical status changed from good to fail in 2019, due to the presence of polybrominated diphenyl ethers (PBDE), which had not previously been included in the assessment.