Pinar del Rio (pēnärˈ dĕl rēˈō) [key], province (1994 est. pop. 700,000), W Cuba, the westernmost province of Cuba. Pinar del Rio is the capital. The province, occupying a narrow area, has an irregular and swampy coast; it is mostly level, with one important mountain range, the Cordillera de Guaniguanico. The chief river is the Cuyaguateje. The traditional industry of Pinar del Rio, Cuba's poorest province, is the growing of tobacco, which is cultivated in the Vuelta Abajo region and is among the world's best. Other agricultural products are of limited importance; mines at Matahambre yield copper, and tourism is also important to the economy.