The volcano of Coatepeque (now Coatepeque Lake), older brother of the present Santa Ana volcano, and father of the rest of volcanoes that make up this eruptive complex, experienced a ferocious period of megatelúrica activity that concluded with a great explosion that left the huge hole Of more than 20 kilometers of radius and about two of depth, that began a long process of catching rainwater and underground to become lake.

Lake Coatepeque is located between the municipalities of Santa Ana, El Congo and Izalco and about 50 kilometers from San Salvador. It is a volcanic caldera, with an approximate extension of 6,500 Ha. Of which 2,500 correspond to the mirror of water (about 25 Km2). In the basin live more than 20,000 people, plus an average of 5,000 monthly tourists who visit the lake.