The Metropolitan Borough of Wirral is a metropolitan borough of Merseyside, in North West England. It has a population of 322,453, and encompasses 62 square miles of the northern part of the Wirral Peninsula. Major settlements include Birkenhead, Wallasey, Bebington, Heswall, Hoylake and West Kirby. Wirral is England's westernmost metropolita…The Metropolitan Borough of Wirral is a metropolitan borough of Merseyside, in North West England. It has a population of 322,453, and encompasses 62 square miles of the northern part of the Wirral Peninsula. Major settlements include Birkenhead, Wallasey, Bebington, Heswall, Hoylake and West Kirby. Wirral is England's westernmost metropolitan borough, faced by the city of Liverpool to the northeast over the River Mersey.