A Site of Special Scientific Interest (SSSI) in Great Britain is a conservation designation denoting a protected area extremely valuable for its flora, fauna, physiological and geological features. SSSI/ASSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in the United Kingdom are based upon them, including national nature reserves, Ramsar sites, Special Protection Areas (SPAs), and Special Areas of Conservation (SACs).
The intentional or reckless damage of a SSSIs features or disturbance of its wildlife, is an offence.
SSSIs include sites such as:
- Species rich grasslands
- Coastal marshes
- Heath lands
- Ancient woodlands
Sites notified for their biological interest are known as Biological SSSIs (or ASSIs), and those notified for geological or physiographic interest are Geological SSSIs (or ASSIs). Sites may be divided into management units, with some areas including units that are noted for both biological and geological interest.
Natural England has responsibility for identifying and protecting SSSIs in England under the provisions of the Wildlife and Countryside Act.
