district, administrative and historic county of Cornwall, southwestern England, near the western tip of England and including the southernmost point of the island of Great Britain. Kerrier district spans the peninsular county of Cornwall and is bordered by St. George's Channel on the north and the English Channel on the south.

The Lizard Peninsula, a heather-covered moorland 200 to 300 feet (60 to 90 metres) high jutting into the English Channel in southern Kerrier district, is the southernmost part of Great Britain. It is composed of Precambrian metamorphic rocks including gniesses, schists, gabbros, and serpentines, the latter quarried for their ornamental value. The coastal scenery of the Lizard Peninsula is magnificent with offshore rocks, rugged cliffs, and small coves.

The north-coastal and central sections are generally a rolling plateau composed of hard sandstone soils. Heavy winds and dampness discourage cereal cultivation there, but dairy cattle graze and fodder crops are grown. Early-season vegetables, fruits, and flowers for the London market are intensively grown in sheltered valleys and coves on both coasts. Wendron Moor, 400 to 800 feet (120 to 245 metres) in elevation, an igneous-based granite intrusive in the centre of the plateau, is used for grazing cattle. From the early 18th century the northern border area of Wendron Moor and the adjacent sandstone plateau was a principal tin-mining area of Cornwall, but tin mining in the area had greatly declined by the late 20th century. The small conurbation of Camborne-Redruth within the northern border area manufactures mining equipment (including rock drills and air compressors) for both local and international markets. Camborne is the administrative centre. Area 183 square miles (473 square km). Pop. (2001) 92,536.