This beautiful crater lake, located between the cities of Masaya and Granada was declared a nature reserve in 1991 and proposed World Heritage site. It was created by a large volcanic eruption over 21,000 years ago. Recently, petroglyphs and artifacts of indigenous peoples have been found in the reserve.

Apoyo Lake has 6 kilometers of diameter and more than 280 meters of depth, being the deepest geological point in Central America. Tourists with various tourist attractions such as dark sand beaches for swimming, hiking, diving, paragliding, boating, and nature. The water of the lake is exceptionally clean and clear and is reputed to have therapeutic qualities for the skin owing to the presence of sulfur and other minerals. It is delightfully warm all year round for swimming.

The reserve houses a tropical dry ecosystem, within the reserve the flora consists of numerous species of plants and tropical dry trees, such as pochote, black rosewood, mahogany, hogplum and guacuco, as well as a large variety and amount of orchids. The fauna consists of mammals such as opossums, giant anteaters, pacas, jaguarundis, Howler and White-faced Capuchin monkeys.

As well as a variety of reptiles such as green iguanas and common boas. Over 200 species of birds have been documented in the reserve are abundant, oropendolas, falcons, hummingbirds, and 65 species of migratory birds are present. Also, various species of butterflies and mollusks. Apoyo lake also contains a variety of fish species, four species of mojarras, which are to be found exclusively in the lagoon.