CASTELLON DE LA PLANA, a city of eastern Spain, capital of the province described above, on the Barcelona-Valencia railway, 4m. from the Mediterranean sea. Pop. (1930) 36,781. Castellon lies on a fertile plain irrigated from the Mi j ures estuary, 5m. S.E., by a rock-hewn Moorish aqueduct. The town, partly encircled by ruined walls, is mainly modern, but contains several ancient convents, an old octagonal bell-tower, 13oft. high, and a 14th century church with an interior painting by Francisco Ribalta, who was born here in 1555. Castellon manufactures porcelain, leather, rope, paper and clothing. Its harbour, El Grao de Castellon, 4m. E., and lately improved, is annually entered by some 400 small vessels, mainly engaged in shipping oranges, almonds and locust beans to Britain and hemp to other parts of Spain. The chief imports are coal and chemical manures. A light railway from Onda connects Castellon and its port with the orange groves to the south-west. Under the Moors Castellon occupied a hill to the north of its present site ; its removal to the plain by James I. of Aragon (1213-76) gave the town its full name, "Castellon of the Plain."