Lake Coatepeque

Lake Coatepeque, located in El Salvador, is a striking blue lake that fills part of a caldera. The caldera was formed by a series of explosive eruptions between 72,000 and 51,000 years ago. Today, the lake is surrounded by homes, restaurants, and other structures, with the city of Santa Ana lying about 15 kilometers to the north.

The lake's water can occasionally take on a bright turquoise hue, which is likely the result of natural mineralization. The surrounding landscape is a mosaic of urban areas, agricultural fields, and volcanic terrain, with the Central American Volcanic Arc stretching over 1,000 kilometers along the Pacific coast.

An astronaut aboard the International Space Station took a photo of the lake and its surroundings on February 10, 2026. The image was captured using a Nikon Z9 digital camera with a focal length of 400 millimeters.