kraj (region), western Czech Republic. It is bordered by Germany on the north and west and by Severočeský, Středočeský, and Jihočeský kraje on the east. It is surrounded by mountains on its external boundaries and contains a series of hilly ranges running southwest to northeast. The region's only lowland areas are the valleys of the Berounka River and its several tributaries that converge in a plain on the regional capital, Plzeň (German: Pilsen).

Corn (maize) for animal feed, hay, wheat, barley, oats, potatoes, and rye are the most important crops grown in the lower areas of the region. Apples, plums, pears, and cherries are the principal fruits; and hogs, cattle, and poultry constitute the main livestock. Forestry is important in the mountains. Coal is Západočeský kraj's main mineral resource, but tin, tungsten, building stone, and kaolin are also extracted. The principal industrial centre is Plzeň, which is also the region's main cultural centre.

Západočeský kraj is renowned for its thermal and mineral water spas. The most famous is Karlovy Vary, founded 1347–58. Area 4,199 square miles (10,875 square km). Pop. (1991 prelim.) 860,311.