 At a significantly higher elevation than the other Cheshire SSSIs and underlain by millstone grit and shale, they contain a variety of upland habitats, predominantly heather moorland, grassland and blanket mire.Ten SSSIs are located in Warrington and the former boroughs of Halton and Ellesmere Port & Neston, in the north-west of the county.These fall within the Urban Mersey Basin natural area, which also covers Greater Manchester and Merseyside.