The Cotswold Water Park is the United Kingdom's largest marl lake system, straddling the Wiltshire–Gloucestershire border, northwest of Cricklade and south of Cirencester. There are 180 lakes, spread over 42 square miles (110 km2).
Strawberry Banks is a 5.06-hectare (12.5-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1993.
Barnsley Warren is a 61.3-hectare (151-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1954 and renotified in 1984. The site is also included in A Nature Conservation Review. It lies in a steep-sided dry valley, east of the A429, northeast of Cirencester in the Cotswolds. The site is listed in the 'Cotswold District' Local Plan 2001-2011 as a Key Wildlife Site (KWS).
Ashleworth Ham is a 104.73-hectare (258.8-acre) biological Site of Special Scientific Interest. It is a large area of grassland on the Severn floodplain, north of Ashleworth in Gloucestershire, England. It is registered as a Site of Special Scientific Interest and was notified in 1974 and renotified in 1985. Ashleworth Ham received this designation because it is one of three sites in the Severn Vale where migratory waterfowl winter.
Brassey is a 2.1-hectare (5.2-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1954 and renotified in 1983. It is situated on the north side of the Windrush Valley, midway between Naunton and Upper Slaughter. The reserve comprises sloping, unimproved limestone pasture. There is a fast-flowing stream. This site is one of the few freshwater marshes in Gloucestershire. The stream joins the River Windrush.
Chaceley Meadow is a 1.8-hectare (4.4-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1954 and renotified in 1993. It lies on the eastern edge of Chaceley village and is about half a mile west of the River Severn.
Daneway Banks is a 17-hectare (42-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1954 and renotified in 1983. It lies half a mile west of Sapperton and is part of a group of wildlife sites in the Frome Valley that includes Siccaridge Wood and Sapperton Canal reserves. The site is in the Cotswold Area of Outstanding Natural Beauty.
Swift's Hill is a 9.15-hectare (22.6-acre) biological and geological Site of Special Scientific Interest in Gloucestershire, notified in 1966 and renotified in 1984.
Salmonsbury Meadows is an 18-hectare (44-acre) biological and geological Site of Special Scientific Interest in Gloucestershire, notified in 1985. The site is listed in the 'Cotswold District' Local Plan 2001-2011 as a Key Wildlife Site (KWS).
Bourton Down is an 11.17-hectare (27.6-acre) biological Site of Special Scientific Interest near Bourton-on-the-Hill in Gloucestershire, notified in 1974. The site is listed in the 'Cotswold District' Local Plan 2001-2011 as a Key Wildlife Site (KWS).
Bushley Muzzard, Brimpsfield is a 1.13-hectare (2.8-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1984.
Crickley Hill and Barrow Wake is a 56.8-hectare (140-acre) biological and geological Site of Special Scientific Interest in Gloucestershire, notified in 1974.
Elmlea Meadows is a 6.9-hectare (17-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1989. The site is listed in the 'Cotswold District' Local Plan 2001-2011 as a Key Wildlife Site (KWS).
Leckhampton Hill and Charlton Kings Common is a 63.8-hectare (158-acre) biological and geological Site of Special Scientific Interest in Gloucestershire, notified in 1954. There are five units of assessment.
Puckham Woods is a 32.38-hectare (80.0-acre) biological Site of Special Scientific Interest in Gloucestershire to the east of Cheltenham near Whittington, notified in 1954. The site is listed in the 'Cotswold District' Local Plan 2001-2011 as a Key Wildlife Site (KWS).
Range Farm Fields is a 12.8-hectare (32-acre) biological Site of Special Scientific Interest in Gloucestershire, near to Gloucester City, notified in 1996.
{{Infobox SSSI |image=[[Image:Carex tomentosa inflorescence.jpg|200px|]] |image_caption=Example - downy-fruited sedge |name=Whelford Meadow |aos=Gloucestershire |interest=Biological |gridref=SP168000 |coordinates = 51.698946°N 1.757592°W |area=1.86 hectare |notifydate=1985 |enref=1003804 }}
Wildmoorway Meadows is a 12.6-hectare (31-acre) biological Site of Special Scientific Interest in Gloucestershire, to the east of Fairford, notified in 1989. The site is listed in the 'Cotswold District' Local Plan 2001-2011 as a Key Wildlife Site (KWS).
Winson Meadows is a 7.93-hectare (19.6-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1974. The site is listed in the 'Cotswold District' Local Plan 2001-2011 as a Key Wildlife Site (KWS).
Mar Field Fen is a Site of Special Scientific Interest, or SSSI, north of Masham, North Yorkshire, England, in a rural area known as Marfield. It is situated on land containing woodland carr, fen, spring-fed marshy grassland and drier calcareous grassland, between the River Ure to the east and Marfield Wetland nature reserve to the west. As "one of the best examples of fen habitat in the Vale of York," it is a protected habitat for a variety of plants, including the common butterwort, a carnivorous plant. There is no public access to this site.
