metropolitan borough, metropolitan county of West Midlands, historic county of Warwickshire, central England, between Birmingham and Coventry. In addition to the historic town of Solihull, the borough comprises Castle Bromwich, Marston Green, Meriden, Shirley, Knowle, Balsall Common, and surrounding areas. Solihull borough, which is mainly suburban but includes some open countryside, began to expand as a residential area for Birmingham in the 19th century, and after 1930 it grew rapidly. The borough's historic buildings include St. Alphege's Church, with its 13th-century chancel, and the 15th-century Packwood House. Although mainly a residential area, Solihull has automobile and other light industries. The National Exhibition Centre (1976) and Birmingham International Airport are both near the centre of the borough. Area 69 square miles (178 square km). Pop. (2001) 199,521; (2006 est.) 203,000.