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).
Thatcham Reed Beds is a 67.4-hectare (167-acre) biological Site of Special Scientific Interest east of Newbury in Berkshire. It is part of the Kennet & Lambourn Floodplain Special Area of Conservation and an area of 14 hectares is a Local Nature Reserve. An area of 35 hectares is managed by the Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust.
Sevenoaks Gravel Pits is a 73.7-hectare (182-acre) biological Site of Special Scientific Interest on the northern outskirts of Sevenoaks in Kent. It is managed by Kent Wildlife Trust as the Sevenoaks Wildlife Reserve and Jeffery Harrison Visitor Centre.
Burham Down is a 110-hectare (270-acre) nature reserve between Maidstone and Chatham in Kent. It is managed by the Kent Wildlife Trust. It is part of the Wouldham to Detling Escarpment Site of Special Scientific Interest and Nature Conservation Review site, Grade I, the Kent Downs Area of Outstanding Natural Beauty, and the North Downs Woodlands Special Area of Conservation.
Brimpton Pit is a 1.6-hectare (4.0-acre) geological Site of Special Scientific Interest west of Aldermaston in Berkshire. It is a Geological Conservation Review site.
Decoy Pit, Pools and Woods is a 17.7-hectare (44-acre) biological Site of Special Scientific Interest south of Aldermaston in Berkshire. An area of 8 hectares is a nature reserve called Decoy Heath, which is managed by the Berkshire, Buckinghamshire and Oxfordshire Wildlife Trust.
Mid Colne Valley is a 132 hectare biological Site of Special Scientific Interest in Harefield in the London Borough of Hillingdon and Denham in South Buckinghamshire. Its main importance lies in its extensive diversity of birdlife in lakes in former gravel pits.
Ruxley Gravel Pits is an 18.7-hectare (46-acre) biological Site of Special Scientific Interest in Ruxley, Orpington, in the London Borough of Bromley, and originally dug between 1929 and 1951. It is also a Site of Metropolitan Importance for Nature Conservation. It is owned by the Environment Agency and managed by Kent Wildlife Trust. Natural England has assessed its condition as "unfavourable recovering".
Frampton Pools is a 59.84-hectare (147.9-acre) biological Site of Special Scientific Interest in Gloucestershire, notified in 1974. The pools are on the edge of the village of Frampton on Severn.
Bassenhally Pit is an 8.6 hectare biological Site of Special Scientific Interest north-east of Whittlesey in Cambridgeshire.
Upper Nene Valley Gravel Pits is a 1,382.4 hectare biological Site of Special Scientific Interest in a chain of flooded gravel pits along 35 kilometres of the valley of the River Nene between Northampton and Thorpe Waterville in Northamptonshire. It is a Ramsar wetland site of international importance, a Special Protection Area under the European Communities Birds Directive and part of the Nene Valley Nature Improvement Area. It is also part of the River Nene Regional Park. Two areas are managed by the Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire, Summer Leys and Titchmarsh Nature Reserve.
Ditchford Lakes and Meadows is a 31.1 hectare nature reserve Northamptonshire. It is managed by the Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire. It is part of the Upper Nene Valley Gravel Pits Site of Special Scientific Interest, Ramsar wetland site of international importance, and Special Protection Area under the European Communities Birds Directive.
Wraysbury No 1 Gravel Pit is a 58.0-hectare (143-acre) biological Site of Special Scientific Interest in Wraysbury in Berkshire. It is part of South West London Waterbodies Ramsar site, and Special Protection Area. The lake has a surface area of 39.6 hectares(97.85 acres). The site has an area of 58.0-hectare (143-acre) and the lake 39.6-hectare (98-acre). The pit was excavated in the 1920s and 1930s with gravel being removed from the site. Over the years plants and wildlife have colonised the area and it is now mature.
Wraysbury and Hythe End Gravel Pits is a 117.2-hectare (290-acre) biological Site of Special Scientific Interest in Wraysbury in Berkshire. It is part of South West London Waterbodies Ramsar site and Special Protection Area.
Higham Ferrers Pits is a 10 hectare nature reserve Northamptonshire. It is managed by the Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire. It is part of the Upper Nene Valley Gravel Pits Site of Special Scientific Interest, Ramsar internationally important wetland site and Special Protection Area under the EC Birds Directive.
Wilson's Pits is a 32 hectare nature reserve west of Higham Ferrers in Northamptonshire. It is managed by the Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire. It is part of the Upper Nene Valley Gravel Pits Site of Special Scientific Interest, Ramsar internationally important wetland site and Special Protection Area under the EC Birds Directive.
West Stow Heath is a 44.3 hectare biological Site of Special Scientific Interest west of West Stow in Suffolk. It is part of the Breckland Special Protection Area under the European Union Directive on the Conservation of Wild Birds.
Cave's Inn Pits is a 5.8 hectare biological Site of Special Scientific Interest south-west of Shawell in Leicestershire.
Hay-a-Park Gravel Pit is a Site of Special Scientific Interest, or SSSI, adjacent to the east side of the town of Knaresborough, North Yorkshire, England. Having been a disused and flooded quarry since the 1970s, it now consists of the large Hay-a-Park Lake and three smaller ponds, besides associated reedbeds, scrub, woodland and grassland. It was designated as a SSSI in 1995 because it supports a number of wintering birds, including a large flock of goosander. This site is "one of the most northerly inland breeding populations of reed warbler in Britain." Hay-a-Park was once part of a royal park, an early landowner being Edward II.
