In the north, its boundary skirts the river Wawa; in the west, it corresponds with the eastern limit of the Nicaraguan highlands; in the south, it is drawn along the river Rama.
Chinandega is the centre of a fertile corn-producing district, and has a large transit trade owing to its excellent situation on the chief Nicaraguan railway.
Issuing from the lake within Nicaraguan territory, the San Juan has a course of 95 m., mostly along the frontier, to the Colorado Mouth, which is its main outfall, and belongs wholly to Costa Rica.
The native Indians, though exterminated in many districts, and civilized in others, remain in a condition of complete savagery along parts of the Nicaraguan border, where they are known as Prazos or Guatusos, in the Talamanca country and elsewhere.
The main Nicaraguan cordillera, which flanks the depression on the east, has often been called the Cordillera de los Andes, from its supposed continuity with the mountain-chains of Panama and the west coast of South America.