Which English peninsula includes the Wirral and lies between the Dee and Mersey estuaries?

The Wirral Peninsula lies between the Dee and Mersey estuaries in northwestern England.

It is bounded by the River Dee to the west and the Mersey estuary to the east, with Liverpool across the Mersey. Most of the peninsula lies in the metropolitan borough of Wirral, while its northern and eastern surroundings connect with parts of Merseyside and Cheshire. Birkenhead is its largest urban centre.

The peninsula combines dense towns, industrial waterfronts, farmland and coastal habitats. The Wirral Way follows a former railway route along the western side, while sites such as Hilbre Island sit near the Dee estuary mouth. Its position helped make the area important to the growth of the Liverpool port complex.

“Wirral” can refer either to the peninsula or to the metropolitan borough, so the geographic and administrative meanings are not identical. The peninsula’s defining physical feature is the pair of estuaries that frame it on opposite sides.