The Wash is the largest bay in England and spans from Gibraltar Point in Lincolnshire, around to the east of Guys Head and to Gore Point in Norfolk where it ends. It is fed by the rivers Steeping, Welland, Witham, Nene and Great Ouse. It covers around 62,000 ha and is the most important coastal site for birds in the UK, as well as being one of the most important and dynamic wetlands for wildlife in Europe.

The Wash also supports important estuarine habitats, including 10.6% of the UK’s saltmarsh (4,800 ha), and 6% of the UK’s mudflat and sandflats (18,000 ha), with the remaining areas made up of other habitats including small areas of sand dunes, vegetated shingle, and coastal lagoons.

The Wash’s value to nature is recognised for its international and global importance. It is designated as Ramsar, Special Protection Area (SPA), Special Area of Conservation (SAC) and Site of Special Scientific Interest (SSSI). It is the UK’s largest site designated for wildlife.

The Wash is home to seven nature reserves, which are managed by the RSPB, Lincolnshire Wildlife Trust, Norfolk Wildlife Trust, and Wild Ken Hill, as well as being designated a National Nature Reserve.

The Wash is a key site used by birds migrating from Africa to the Arctic (‘East Atlantic Flyway’).

It supports a thriving fishery industry (primarily cockles, mussels, and brown shrimp), the busy ports of Boston and King’s Lynn, and maintains the fertile soils of the surrounding farmland.