Dominican Republic - Geography

Tactical, tracked vehicles, light armored vehicles, or foot travel are efficient in the lowlands. However, maneuverability is limited in the western interior highlands, particularly in urban or heavily forested areas. The rugged terrain impedes ground transport, particularly north-south movement.

The Dominican Republic’s terrain features high, rugged mountains; highland regions; some extensive lowlands; and multiple isolated valleys and basins. The eastern lowlands region is a flat-to-rolling, cultivated plain in the southeast. The northern highlands area is a mountain range containing steep slopes and deep valleys. The central and southern highlands are divided by several mountain ranges and mountain streams, which flow through deep canyons.

The Dominican Republic occupies the eastern two-thirds of the Caribbean island of Hispaniola, which it shares with Haiti. Hispaniola is 1,100 kilometers (685 miles) southeast of the southern tip of Florida. Covering 48,730 square kilometers (18,815 square miles), the Dominican Republic is approximately twice the size of New Hampshire. The country has a wide variety of terrain and vegetation, ranging from deserts in the southwest to alpine forests in the central mountains. Sugarcane fields are prevalent in the coastal plains in the north and east, and banana plantations occupy most of the tropical peninsula of Samana. The southern coast features pebbled beaches and rocky cliffs.

The border between the Dominican Republic and Haiti follows an irregular line from north to south, but the relief features of Hispaniola are oriented on a northwest-southeast axis. As a result, the two countries share the principal mountain ranges and intervening valleys. The mountains cause internal communications difficulties, and numerous streams and rivers impede cross-country movement. The valleys between the Dominican Republic and Haiti enable unrestricted movement, leading to border incidents and illegal crossings.

The Dominican Republic has extensive, rugged highlands separated by parallel valleys. A narrow, coastal plain widens to the southeast. The highest mountains in the Caribbean are in the Dominican Republic. Three of the four primary ranges are oriented northwest-to-southeast. These mountains and the single east-west oriented range are all located in the central region. Together they comprise 65 percent of the national area.

Cordillera Central is the island’s main geographic feature. It extends from the central southern coast near Santo Domingo northwest into Haiti; the northern limit is the Valle del Cibao. Cordillera Central constitutes the Dominican Republic’s principal watershed — its ridges crest at 1,525 to 2,440 meters (5,000 to 8,000 feet), but individual peaks can rise to greater heights. Slopes have gradients as steep as 40 percent.

Streams in Cordillera Central have created canyons and rocky gulches that restrict transit in many places. Most of the highland streams have winding courses that contain numerous rapids and low waterfalls. Stream banks are usually high and steep, and water levels rise rapidly during tropical storms. Flash flooding is another problem, resulting from deforestation and erosion. Coniferous forest and scrub cover most of the Cordillera Central, except in less rugged areas and mountain valleys, where there is also pasture and croplands.

South of the Cordillera Central are two parallel mountain ranges: the Nieba Mountains (Sierra de Neiba) and the Baoruco Mountains (Sierra de Baoruco). These ranges begin as steep coastal slopes on Neiba Bay (Bahia de Neiba) in the southwest and continue northwest and across the border into Haiti. Both crest at elevations between 900 and 1,200 meters (3,000 and 4,000 feet), with peaks as high as 1,800 meters (6,000 feet). The Rio Yaque del Sur separates the eastern part of the Neiba Mountains (referred to as Sierra de Martin Garcia) from the remainder of the range. The forests in the southernmost ranges consist of spiny brush, mixed deciduous trees, and broad leaf evergreens.

The Enriquillo Basin is a relatively broad, interior lowland plain separating the Neiba Mountains from the Baoruco Mountains. This plain is approximately 1,200 square kilometers- (470 square miles) long and mostly below sea level; it extends from Neiba Bay to the Haitian border, where it merges with the region known as the Cul-De-Sac (dead end). The area is semiarid to arid, distinguished by saltwater lakes and a series of terraces on both sides of the valley.

The Neiba Mountains and the Cordillera Central parallel each other and are separated by a highland valley, the Valle de San Juan, which extends across the Haitian border, where it is known as the Central Plateau. Elevations are generally below 150 meters (500 feet) in the eastern section and 300 meters (1,000 feet) or more in the west.

The Cordillera Oriental is a narrow band of hills east of Cordillera Central. It extends east-to-west 137 kilometers (85 miles) from the Atlantic Coast along the southern shore of Samana Bay (Bahia de Samana) to the foothills of the Cordillera Central, north of Santo Domingo. Elevations in the Cordillera Oriental are typically less than 300 meters (1,000 feet), except in the extreme east where some peaks rise to higher than 600 meters (2,000 feet).