Province in the extreme W. of Argentina; has the Andes in the W., Aconcagua (23,500 ft.), the highest peak in the New World, otherwise is chiefly worthless pampa, fertile only where irrigated from the small Mendoza River; there vines flourish; copper is plentiful, coal and oil are found. Mendoza, the capital, 640 m. W. of Buenos Ayres by rail, is on the Trans-Andine route to Chili, with which it trades largely; suffers frequently from earthquakes.