The land near the city of Ahuachapán is pockmarked with craters and covered with recent lava flows.
Meanwhile, ageothermal fieldfeeds geysers, heatsmineral pools, and powers a long-operating energy plant.
The area is part of a volcanic landscape that stretches more than 1,000 kilometers along the Pacific coast from Guatemala to Panama, composing the Central American Volcanic Arc.
On the right side of the image, Santa Ana stands at 2,381 meters above sea level as the country’s tallest volcano.
Its summit features several crescent-shaped ridges surrounding a hot, acidiccrater lake.
The volcano remains active, with small to moderate explosive eruptions recorded since the 16th century.
Its most recent significant eruption,in 2005, launched a dense gas and ash column high in the air and sentlaharsdown its slopes.
In 1770, another volcano began forming on Santa Ana’s southern flank.
Izalcogrew into a steep-sided stratovolcano through frequent eruptions over the next two centuries.
Its regular activity—including Strombolian eruptionsand lava fountains—earned it the nickname “Lighthouse of the Pacific,” as people at sea were reported to witness its glowing emanations.
The “lighthouse” has since powered down, with Izalco’s most recent activity occurring in 1966.
A line of forested, dimpled stratovolcano peaks arcing across the scene forms the Apaneca Range.
There are no recorded eruptions of these volcanoes in the Holocene, but persistent geothermal activity along the range manifests in the form offumaroles, hot springs, and steam vents.
Sudden and deadly steam explosions occasionally occur in the area, including ablast in October 1990near the range’s Laguna Verde volcano.
More recently, a2025 steam eruptionnear a popular hot springs facility spurred evacuations and damaged infrastructure.
Though sometimes hazardous, the region’s heat source has also been tapped forgeothermal power.
The Ahuachapán Geothermal Power Plant has operated since 1975, leveraging groundwater naturally heated to around250 degrees Celsius and local fault systems.
By the early 1980s, the plant was producing40 percentof El Salvador’s electricity.
Somescholars notethat this high level of production coincided with a period of civil unrest and population growth in the region.
NASA Earth Observatory image by Michala Garrison, using Landsat data from theU.S. Geological Survey. Story by Lindsey Doermann.
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Jiménez Majano, J.E.Fifty Years of Operation at the Ahuachapán Geothermal Field. Proceedings, 50th Workshop on Geothermal Reservoir Engineering.
NASA Earth ObservatoryLake Coatepeque. Accessed May 4, 2026.
Smithsonian Institution Global Volcanism Program, Santa Ana. Accessed May 4, 2026.
Smithsonian Institution Global Volcanism Program, Izalco. Accessed May 4, 2026.
Volcano LiveApaneca Range. Accessed May 4, 2026.
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