The composer and poet Ivor Gurney wrote from the trenches in Flanders of "making Musical History for England, and out of Gloster stuff". He was not alone in receiving musical inspiration from this particular landscape. Naturalist Lionel Kelleway looks at why the county of Gloucester, which takes in the Cotswold Escarpment, the Severn Vale, the Royal Forest of Dean and the Malvern Hills, was so special in creating a national identity for 20th-century British music. Producer Paul Evans Repeated on Sunday at 12.15am