Blackhall Rocks & Cross Gill Nature Reserve

About

This coastal site is as important for both its geology and wildlife. The cliffs and coastal area feature natural exposures of reef-limestone, set down 250 million years ago in the waters on the ancient Zechstein Sea, glacial boulder clays and beds of gravel.

The caves in the southern section of cliffs are the largest in Durham’s magnesium limestone coastline.

The site attracts a variety of insects with 15 species of butterfly recorded, including Durham brown argus, and the rare cistus forester moth.

This unique geology supports a very rich flora on the cliffs and coastal grassland, including species such as quaking grass, rockrose and bloody cranesbill. The wet gullies contain many locally rare plants, such as butterwort, grass of Parnassus and bird’s eye primrose. The slopes of Blue House Gill host low growing scrub with privet and willows, which support breeding birds and provide a stop off point for spring and autumn migrants.