Wirral, metropolitan borough (1991 est. pop. 322,100), NW England, on the peninsula between the Mersey and Dee estuaries, in the Greater Manchester metropolitan area. Sometimes referred to as "the dormitory of Liverpool," it contains many high-income residential developments, as well as some light industry and agricultural land. The coastal areas are mainly relegated for recreational purposes; formerly the area was a royal forest and game preserve. Arrowe Park was the site of the First Worldwide Boy Scouts Jamboree in 1929. Heswall parish was the birthplace of Emma Hamilton.