departamento, western Colombia, rising from the Pacific lowlands across the Andean Cordillera Occidental to encompass the valley of the upper Cauca River. The department is a leading producer of sugar, rice, tobacco, and coffee. Buenaventura is the nation's chief Pacific port, through which the major portion of Colombia's coffee is exported. The Pan-American Highway and the Puerto Berrío–Popayán railroad run along the Cauca Valley, linking Cali, the department capital, with major cities to the northeast. Area 8,548 square miles (22,140 square km). Pop. (2007 est.) 4,257,741.