Dartmoor, a great granitic upland in Devonshire, the source of nearly all the principal rivers of the county, remarkable alike for its wild and rugged scenery, its antiquities, its wide, solitary, trackless wastes, and its mineral products. It is upwards of 130,000 acres in extent, the extreme length from north to south being 25 miles, and the extreme breadth 20. The central portion is the ancient royal forest of Dartmoor, whose rights belong to the Duchy of Cornwall; this is surrounded by a belt of open country, once known as the 'Commons of Devonshire,' but portions of which have been enclosed. The attempts to cultivate Dartmoor itself have been very few, and the northern quarter for miles shows no trace of man. The valleys through which the rivers descend to the lowland country are singularly fertile, and at times full of beauty. The moor itself affords valuable mountain pasture to cattle, sheep, and large numbers of half-wild ponies. The average height of Dartmoor above the sea is upwards of 1200 feet, but its highest point, High Willhayes, is 2039 feet; and the next, Yes Tor, 2030. The hills are commonly called tors, and for the most part have granite crests, weathered into grotesque and picturesque shapes. Dartmoor is rich in minerals - tin, copper, iron, manganese, gold, and china-clay or kaolin, this last much the most important nowadays. Dartmoor is unrivalled in England in the extent and character of its prehistoric and rude stone antiquities. The chief centre of population is Prince Town, where is a prison, built (1806) for prisoners of war, and adapted (1855) to its present purpose of a convict prison. See works by Rowe (1856), and Page (1889).