Cibao Valley, valley in the northern Dominican Republic. It extends about 145 miles (235 km), from Manzanillo Bay in the west to Samaná Bay in the east. The mountain ranges of the Cordillera Septentrional and the rugged Cordillera Central bound the Cibao Valley on north and south, respectively. It has two climatic zones: the drier western section, traversed by the Yaque del Norte River, has savanna vegetation, with patches of low, thorny bushes; the east, watered by the Yuna River, is the humid, fertile La Vega Real region, a name given it by Christopher Columbus. Chief crops are, in the west, wheat and, with modern irrigation, rice and bananas; in La Vega Real, coffee, tobacco, cacao, corn (maize), and rice are grown. The Cibao Valley is the country’s most densely settled region. European colonization began there in 1494, when Columbus searched for gold in La Vega Real on his second voyage.