CASTLEFORD, an urban district in the Osgoldcross parliamentary division of the West Riding of Yorkshire, England, on the river Aire near its junction with the Calder, 9 m. S.E. of Leeds, on the North-Eastern and Lancashire & Yorkshire railways. Pop. (1901) 17,386. Large glass-bottle and earthenware-jar works, chemical works, and neighbouring collieries employ the inhabitants. Here was the Roman village or fort of Lagecium or Legeolium; and though visible remains are wanting, a number of relics have been discovered.