Wooded river valley retaining important and coherent relict remains of 15 of the Rivelin Valley's 20 water powered sites. The following description relates to the entire valley: "Much of this part of the valley is steep-sided and narrow; this, and the extent to which it is physically cut off from the old centre of Sheffield by the high ground of Crookes and Walkley, explains why 14 of the 20 appear not to have been developed before the 18th century" . . . "Although buildings only survive only at Mousehole Forge, and the remnants of structures elsewhere are sparse, the earthworks present an excellent introduction to the methods of Sheffield millwrights in their harnessing of water power. All the wheels are fed by bypass systems, and in most cases sufficient survives of weirs, goits and dams to show how these were arranged. Several shells of buildings remained up to 1939, and a few until 1945" (condensed from Crossley 1989, 50). In addition to the remains of the mill systems described in Crossley (ibid) this polygon includes associated workers cottages and church at 'Rivelin Glen Cottages' and probably related stone quarries (for millstones) at 'Millstone Edge Rough' (scrubland) and Rivelin Glen Quarry (now a masons yard). Since its industrial abandonment the tree cover within the valley has significantly increased according to successive OS mapping sets. This semi natural secondary woodland allows for partial legibility of the probable pre industrial past character of this area.