The Wash is a large estuary located on the east coast of England, primarily in the counties of Norfolk and Lincolnshire. It is formed where the River Nene and River Welland meet the North Sea, creating a unique habitat for various wildlife. The area is known for its rich biodiversity, including numerous bird species, making it a popular spot for birdwatching. The Wash covers approximately 620 square kilometers and is characterized by mudflats, salt marshes, and shallow waters. It is also significant for its fishing industry, particularly for crabs and mussels. The estuary is a designated Site of Special Scientific Interest (SSSI) due to its ecological importance.