The River Roch is a historic waterway flowing through the heart of Greater Manchester in northwest England, originating on Chelburn Moor before winding its way through the towns of Littleborough, Rochdale, Heywood, and Bury before joining the River Irwell at Radcliffe. Stretching approximately 100 miles in length, the Roch drains a substantial catchment fed by numerous tributaries including the River Spodden, River Beal, Naden Brook, and Hollins Brook, among many others. The river passes through a landscape shaped by both its moorland headwaters and the post-industrial urban corridor it traverses, giving it a character that blends upland freestone river qualities in its upper reaches with more lowland characteristics as it descends toward its confluence with the Irwell. The name itself is thought to derive from ancient Brittonic roots meaning "River of the great wood" or "River opposite the wood," reflecting the heavily wooded landscape that once defined this part of Lancashire.