Louth (louth) [key], town (1991 pop. 14,093), in the Parts of Lindsey, Lincolnshire, E England, on the Lud River. Although a canal was built to the Humber estuary in the 18th cent., Louth is no longer an important river port. The town's industries include trading, the processing of farm produce, and the manufacture of agricultural implements, malt, and lime. Alfred Tennyson was a pupil at the 13th-century grammar school (rebuilt 1869). There are ruins of a Cistercian abbey founded in 1139; for centuries Louth was an important religious center. The parish church of St. James, noted for its spire, dates from the early 16th cent. The first protests of the Pilgrimage of Grace took place in Louth in 1536.