Furness, peninsula, 15 mi (24 km) long and 4 mi (6.4 km) wide, Cumbria, NW England, between the estuary of the River Duddon and Morecambe Bay. The term is also applied to areas N of Morecambe Bay that are part of the Lake District. In the southwest are virtually extinguished iron mines, which gave rise to the great steelworks formerly centered on Barrow-in-Furness. Farming and tourism are the peninsula's primary industries. Furness Abbey (now in ruins), near Barrow, was a wealthy institution founded by the Benedictines in 1127.