Site of Special Scientific Interest

Arlington Reservoir, a 99.4 hectare (245.6 acre) biological SSSI in Arlington, East Sussex

A Site of Special Scientific Interest (SSSI) is a type of legal conservation given to an area in the United Kingdom. They are sites of biological or geological interest, or both.

A Site of Special Scientific Interest (SSSI) is a special piece of land chosen because of its important plants, animals, or natural features. It's picked under a law called the Wildlife and Countryside Act (1981). Only places chosen under this law after 1981 are counted.

SSSIs are really special areas in England where you find lots of unique and rare plants, animals, and natural things. They're carefully mapped out on special maps made by the Ordnance Survey.

Any activity which might affect an SSSI is illegal unless the appropriate planning body gives permission. Owners of land must do what needs to be done to protect an SSSI which sits on their land. There may be grants available to help owners look after the site.