Blackstone Edge (/ˈblækstən/ BLAK-stən) is a gritstone escarpment at 472 metres (1,549 ft) above sea level in the Pennine hills surrounded by moorland on the boundary between Greater Manchester and West Yorkshire in England.

[1] Blackstone Edge contains evidence of prehistoric activity with the presence of three cup marks on an outcrop of rock 150 metres (490 ft) north west of the (later) Aiggin stone identified by Archaeological Services WYAS.

[4][5] The Aiggin Stone, a gritstone pillar, possibly a way-marker, stands alongside the road, which may also have seen later use as a packhorse route, and marks the county boundary.

During the English Civil War, the Parliamentarians sent 800 men to fortify Blackstone Edge; John Rosworm came from Manchester to direct the construction of defences.

From the summit one can see Manchester city centre, Winter Hill in the West Pennine Moors, and the mountains in North Wales in clear weather.