Puerto Rico - Geography

Puerto Rico is the smallest of the Greater Antilles chain, which also includes Cuba, Jamaica, and Hispaniola (Haiti and the Dominican Republic). Puerto Rico is 145 kilometers (90 miles) from the Dominican Republic to the west and 67 kilometers (40 miles) from the U.S. Virgin Islands to the east. It is 1665 kilometers (1,000 miles) southeast of Miami and 2840 kilometers (1,700 miles) south of New York City. On the north and east side is the Atlantic Ocean, and on the south and west is the Caribbean Sea. It is positioned at the north end of a group of lesser islands that form an arc running down to Venezuela 847 kilometers (525 miles) to the south.

They are called the Lesser Antilles and include the U.S. and British Virgin Islands, French Guadeloupe, Martinique, and numerous other islands down to Grenada, Barbados, and Trinidad. All totaled, in the Greater and Lesser Antilles, there are approximately 7,000 islands that make up what are called the West Indies.

The land area of Puerto Rico and adjacent islands is 8897 square kilometers (3,435 square miles). It is 56 kilometers (35 miles) north to south, 176 kilometers (110 miles) east to west, and is rectangular in shape. Puerto Rico is somewhat smaller than the state of Connecticut. Its coastline is 500 kilometers (311 miles) with numerous harbors and beaches. Its land cover is variable, with much of the center of the island consumed by high mountains (40 percent), surrounded by foothills (35 percent), and a narrow coastal plain (25 percent). Virtually all of the coastal plain is in intensive agriculture, roads, or under urbanization. By 2002 some 41.6 percent of the island was covered by closed forest, 36.7 percent is in pasture and grassland, 5.9 percent is in agriculture, 2.4 percent is in coffee plantations, 10.5 percent is urban/developed, and 3.9 percent is in various other categories including mines, rock/sand areas, salt and mudflats, emergent wetlands, and water bodies. Approximately 5 percent of Puerto Rico’s forest area is under protection.

There are a variety of ecosystems distributed laterally and vertically according to topography, altitude, soils, rainfall, and a variety of other factors. The island lies directly in the path of the trade winds that blow from the Atlantic Ocean to the east. This assures a fairly reliable source of rain and occasionally a hurricane or two. The presence of high mountains creates a very interesting rainfall pattern resulting in the creation of an orographic rain shadow on the Caribbean side of the central mountain ranges, and some rain shadow valleys in the interior sections of the mountains.

The highest altitude on the island is 1338 meters (4,389 feet) in the Cordillera Central range at Cerro de Punta, and there are numerous peaks over 915 meters (3,000 feet). Cerro de Punta is just north of Ponce within the Toro Negro Commonwealth Forest and can be accessed by Route 143 (Luis Muñoz Marín Panoramic Highway). Mountains can be seen from anywhere on the island. The entire center of the island is a continuous series of mountains that basically cuts the island in half as they run east to west from Humacao to Mayagüez. Approximately 25 percent of the island is above 305 meters (1,000 feet) altitude.

The high mountains exhibit high degrees of slope to the south and east, and the north slopes are heavily eroded with numerous river valleys. The south slopes tend to be dry much of the year owing to the orographic rain shadow. During tropical storms and hurricanes, rivers on the south coast may become rapid torrents that flood extensive areas and often kill domestic grazing animals or human squatters living in the dry riverbeds or flood plains.

The Cordillera Central has a break in the area of Caguas, and the mountain range located northeast is the Sierra de Luquillo. This range also has a series of peaks in excess of 915 meters (3,000 feet), and these peaks experience the highest amounts of rainfall on the island. The Luquillo range includes the El Yunque National Forest, also designated as the Luquillo Experimental Forest and known as the world-famous Luquillo Rain Forest or El Yunque. This 11 200-hectare (28,000-acre) forest is a biosphere reserve site and attracts about three quarters of a million visitors per year.

The soils of the coastal plain are conducive to agriculture, and much of it was cleared in the 17th and 18th centuries for sugarcane. Adjacent to the coast, the land is fairly level and has been converted to agriculture, urban development, and transportation corridors. Periodically, there are rocky promontories and karst foothills such as those near Arecibo, Fajardo, Cabo Rojo, and Guánica. Sand dune areas and beaches such as at Isabela, Piñones, Luquillo, and Boquerón dot the coastline.

The rivers that run north from the Cordillera Central in the karst area produce deep cuts in the landscape owing to differential rates of erosion in the limestone. Some of the rivers periodically run underground in association with caves. There are thousands of caves and sinkholes in the region.

Puerto Rico’s geological formations have yielded very few mineable mineral resources. In the early 1500s, gold was mined, but gold was basically gone by the 1570s. Some commercial gypsum, dolomite, and phosphate have been mined. Today, extensive areas of aggregate and road gravel are being consumed.