area of about 80 square miles (210 square km) west of the River Trent in the unitary authority of North Lincolnshire, historic county of Lincolnshire, England. A tract of low flatland less than 100 feet (30 metres) above sea level, it was formerly surrounded by fens. Drainage works, begun in the 17th century by Cornelius Vermuyden and subsequently extended and improved, have transformed the area into one of high fertility. The chief settlement is Epworth, the birthplace of John and Charles Wesley, founders of Methodism, whose father was rector of the parish; the church survives, and the restored rectory is maintained as a museum.