borough (district), administrative and historic county of Lancashire, northwestern England, bordering on the Irish Sea north and east of the resort of Blackpool. The borough, named for the River Wyre, which crosses and drains it, is generally a low coastal plain. Formerly occupied by pockets of marshland, much of the plain has been reclaimed and is now intensively cultivated. Extensive sand beaches have formed offshore of the port and resort of Fleetwood at the mouth of the Wyre in the northwest. The eastern limits of the borough extend into the moor uplands of the Pennines, and most of the borough is rural and agricultural. Most of the population is concentrated near the coast at Fleetwood, Thornton Cleveleys, and Poulton-le-Fylde. Fleetwood is the major fishing port on the west coast of England and is an important port for containerized shipping. Chemicals, plastics, and leather goods are the principal products manufactured at Fleetwood. Retired people favour the seaside resorts of Thornton Cleveleys and Fleetwood. Poulton-le-Fylde is both the local agricultural market centre and the borough's administrative centre. Area 109 square miles (283 square km). Pop. (2001) 105,584.