In the Maribios district occur several volcanic lakelets, such as that of Masaya, besides numerous infernillos, low craters or peaks still emitting sulphurous vapour and smoke, and at night often lighting up the whole land with bluish flames.
The capital is Managua (pop. 1905, about 30,000); other important towns are Leon (45,000), Granada (25,000), Masaya (20,000), Chinandega (12,000), and the seaports of Corinto (3000) and Greytown (2500).
Lake Masaya occupies an extinct crater; the isolated volcano of Masaya (3000 ft.) on the opposite side of the lake was active at the time of the conquest of Nicaragua in 1522, and the conquerors, thinking the lava they saw was gold, had themselves lowered into the crater at the risk of their lives.