Wicken Fen

Wicken Fen is a 254.5 hectare biological Site of Special Scientific Interest west of Wicken in Cambridgeshire. It is also a National Nature Reserve, and a Nature Conservation Review site. It is protected by international designations as a Ramsar wetland site of international importance, and part of the Fenland Special Area of Conservation under the Habitats Directive.
A large part of it is owned and managed by the National Trust.
It is one of Britain's oldest nature reserves, and was the first reserve cared for by the National Trust, starting in 1899. The first parcel of land for the reserve was donated to the Trust by Charles Rothschild in 1901. The reserve includes fenland, farmland, marsh, and reedbeds. Wicken Fen is one of only four wild fens which still survive in the enormous Great Fen Basin area of East Anglia, where 99.9% of the former fens have now been replaced by arable cultivation.

Wikipedia