The largest county in England, is divided into three Ridings (i. e. thirdings or thirds) for administrative purposes, North, East, and West, with a fourth called the Ainsty, under the jurisdiction of the Lord Mayor and aldermen of York; of these the West is the wealthiest and the most populous; contains a large coal-field, and is the centre of the woollen manufacture of the county; the East being mainly agricultural, with iron-works and shipbuilding-works; and the North mainly pastoral, with industries connected with mining and shipping. Leeds is the largest town.