Alde–Ore Estuary is a 2,534 hectare biological and geological Site of Special Scientific Interest which stretches along the Suffolk coast between Aldeburgh and Bawdsey, and also includes parts of the Alde, Ore and Butley Rivers.

[10][11] It includes two Geological Conservation Review sites, "Orfordness and Shingle Street" and "The Cliff, Gedgrave",[12][13] and two nature reserves managed by the Suffolk Wildlife Trust, Alde Mudflats and Simpson's Saltings.

[19] Natural England describes the scientific interests of the site as "outstanding and diverse".

Habitats include grassland, fresh water, ditches, reedbeds, saltmarsh, mudflats, brackish lagoons, and the second largest and best preserved area of vegetated shingle in Britain.

Gedgrave Cliff has fossiliferous strata dating to the early Pliocene Coralline Crag Formation.