Lago de Coatepeque is a lake in a volcanic crater located east of the Volcano Santa Ana, the most famous volcano in El Salvador, about 18 kilometers south of the city of the same name. The lake is one of the largest lakes in the country. On the lake, there is the island of Teopan, which is believed to have been important for the Mayan civilization. With about 60,000 visitors a year, don't expect crowds, but great fun.