Final answer:
Lake Ilopango and Cerron Grande Reservoir are located in El Salvador, which features a range of natural landscapes including volcanic lakes and large reservoirs.
Step-by-step explanation:
Lake Ilopango and Cerron Grande Reservoir are both located in El Salvador. Lake Ilopango is a crater lake which fills an 8 by 11 km (5.0 by 6.8 mi) volcanic caldera in central El Salvador, on the borders of the San Salvador, La Paz, and Cuscatlán departments. The Cerron Grande Reservoir, also known as Embalse Cerrón Grande, is a large reservoir created by the Cerrón Grande Dam on the Lempa river in northern El Salvador. This country, though small in size, is home to diverse natural landscapes including these impressive bodies of water.