Central Region

The Central Region is the second largest subdivision of the country and the one that exhibits the greatest morphologic and biological diversity. It stretches from the Coco River to the San Juan River. Geologically speaking, however, the area located north of the point of origin of the Coco River is different in composition from the rest. Within the Central Region, two macro systems can be distinguished: the Segovian Mountain System and the Central Shield.

Segovian Mountain System

The Segovian Mountain System is the oldest region of Nicaragua. It differs from other systems both geomorphologically as well as physiographically. The slopes of the mountains found here are sharp and the soils of its valleys contain white quartz. These quartz deposits are the product of magma that cooled off within the earth’s crust over thousands of years and has been exposed by erosive processes wearing out of the layers on top over more thousands of years. Its plateaux have been renewed by more recent emergences, and its countless mineral ores (gold, silver, and copper, among others) make the area economically rich.

Within the Segovian Mountain System we can distinguish two main ranges: Dipilto, following a west-east orientation; and Jalapa, with an southwest-northeast orientation. The mountains in these two ranges have an average altitude of 1,700 meters and contain the highest peaks in the country. The tallest mountain is Mogoton, towering 2,017 meters above sea level.

Other mountain groups in the Segovian Mountain System are Quilali-Telpaneca, Murra hills, and the Macuelizo Mountains, all with altitudes ranging between one thousand and fifteen hundred metres above sea level.

The Central Shield

The Central Shield exhibits a triangular shape and extends from the southern bank of the interior portion of the Coco River to the San Juan River. This area used to be the edge of the North American continent several million years ago.

Its origin is volcanic and it can be traced back to the Tertiary Period. The Shield itself is a very large plateau, which declines in altitude from north to south and west to east from seven hundred to two hundred metres. Deep valleys and canyons are found in the Shield, product of erosion caused by the eastward-flowing rivers. Sharp mountains rise up to 1,800 metres in altitude.

The Central Shield presents a variety of formations derived from mountains of volcanic origin that have been subjected to the erosive action of wind and water and soil renewal. As a consequence, physiographically it presents conical hills, monolithic formations, deep canyons, and so on. Soil renewal has also produced table-top plateaux which are separated from each other by narrow canyons with violent waterways, some of which have widened to create valleys and alluvial plains covered with rock fragments from the surrounding mountains.

Cross-sectional sketch of Nicaragua

Three main mountain systems can be observed in the Central Shield: Isabelia, Dariense, and Chontale

Isabelia, following an east-west direction, extends from Yali to Pe`lanca, and ending at the point of origin of the Waspuk and Bambana Rivers. It is the longest and sharpest of the three systems. It produces four branches to the north, separated by the main tributaries of the Coco River. The most important of these branches is the Kilambe due to its height (1,750 meters in altitude), and the Pispis Mountains, where the mining districts of Siuna and Rosita are located. It contains large forest reserves as well as being rich in gold, silver, and iron. On the western portions of the Isabelia sys-tem there are extensive coffee plantations.

Dariense, more accessible than Isabelia, is more economically important. It divides the courses of the Tuma and the Grande the Matagalpa Rivers. It is formed by a series of branches with different geographic orientations (Guasguali, Datanli, Guabule, and Apante). Its economic advantages consist mainly in coffee production and the harvesting of precious woods found in the cloud forests. Its highest peaks are Chimborazo (1,688 meters) and Cerro del Diablo (1,640 metres).

Chontalei> is made up of a series of plateaux and hills that rise up south of the Grande de Matagalpa River. These go down in height as they venture southward. It has been greatly deforested by access roads for livestock production. The deforestation has aided the erosive action of water. While coffee is cultivated in the higher points, most of its economic activity is centred on livestock production given its extensive grasslands areas. To the south, one finds forest reserves. The furthest points of the Chontaleountain system are the Amerrique Mountains and the Yolaina hills.

Among others, some subdivisions of the Central Shield also worth mentioning are:

a) the foothill plains of Somotillo and San Miguelito, an area three-hundred kilometres in length and thirty kilometres wide. These plains have partially arid sections. Crops cultivated here are corn, beans, and cotton, as well as grasslands for livestock production closer to the Department of Chontales. In San Miguelito, however, its proximity to Lake Nicaragua makes the soils swampy and rice production is preferable to livestock.

b) to the West we find the Cerros de Achuapa, with gold and copper deposits; El Sauce mining district; Santa Rosa del Per with clay deposits; the Estrada Plateau, with wheat, corn, and lumber production; and de Cerros de Jicotepe, where livestock production is important.

c) to the northeast we can see the Sierra de la Botija, along the Honduran-Nicaraguan border, with gold, silver and copper mines; and the Tepesomoto mountains, with livestock production and varied agriculture.

d) alluvial plains extend north of Lake Managua all the way to the Somoto plains, following the route of the Pan-American highway. Some of these plains are semi-arid. The main ones are: Sebaco, at four hundred and fifty meters in altitude, with production of rice, vegetables, corn, and beans; Esteli, at eight hundred meters in altitude, with poor soils; and the Somoto valley at an altitude of seven hundred meters, which has suffered heavy erosion due to insensitive human activity.

Caribbean Region

Almost the whole eastern section of the country is made up by a huge stretch of lowlands that vary in altitude from five hundred meters to sea level. The northern border of this region is the Coco River, while the southern is the San Juan River. The width of these lowlands varies as well, from seventy kilometers in the south to one hundred and twenty in the north. Nonetheless, at some points the lowlands go deep inland as they blend with the valleys formed by the great rivers flowing from the Central Highlands.

There are a few small hills that crop up among the dense jungles and pine-covered plains of the Caribbean. Of significance we should mention Wawashan (553 meters) and the Blue Volcano, located just west of Pearl lagoon, in between the Grande de Matagalpa and Kurinwas rivers. The Blue Volcano is a small promontory showing three craters and was discovered very recently (1969) by the crew of a small plane flying at low altitude.