Thompson Water, Carr and Common

Thompson Water, Carr and Common is a biological Site of Special Scientific Interest north of Thetford in Norfolk, England. Most of it is managed by the Norfolk Wildlife Trust as Thompson Common. It is a Nature Conservation Review site, Grade I, and part of the Norfolk Valley Fens Special Area of Conservation. It is crossed by the Great Eastern Pingo Trail Local Nature Reserve.
This grassland site, located in the valley of a tributary of the River Wissey, contains a number of ponds left by melted pingos: damp, water-filled depressions formed by the melting of ice within these geological formations at the end of the last glaciation. It also features a lake called Thompson Water, which, along with its surrounding reed swamp, is important for breeding birds.
The site is open to the public.