Farming, and in particular sheep farming, has been the major industry in the region since Roman times. The breed most closely associated with the area is the tough Herdwick, with Rough Fell and Swaledale sheep also common. Sheep farming remains important both for the economy of the region and for preserving the landscape which visitors want to see. Features such as dry stone walls, for example, are there as a result of sheep farming. Some land is also used for silage and dairy farming.