Muggleswick, Stanhope and Edmundbyers Commons and Blanchland Moor is a Site of Special Scientific Interest in County Durham and Northumberland, England.

The dry heath is dominated by heather, Calluna vulgaris, and wavy hair-grass, Deschampsia flexuosa; the regionally rare bearberry, Arctostaphylos uva-ursi, is found on the higher parts of Blanchland Moor.

Other noteworthy plants are the nationally scarce pale forget-me-not, Myosotis stolonifera, and the regionally rare round-leaved crowfoot, Ranunculus omiophyllus, and ivy-leaved bellflower, Wahlenbergia hederacea, all of which occur in the vicinity of streams, and the nationally scarce spring sandwort, Minuartia verna, one of a number of metallophytes that occur on old spoil heaps around disused lead-mines on Stanhope Common.

[1] As with the rest of the North Pennines moorlands, of which these areas form part, the site is home to nationally important breeding populations of a number of birds.

Three species—merlin, Eurasian golden plover and short-eared owl—are listed in Annex 1 of the European Commission's Birds Directive as requiring special protection; the high density of merlin is particularly noteworthy.