Note: Single-source report; awaiting corroboration.
Western El Salvador's volcanic terrain near Ahuachapán features numerous craters, recent lava flows, and a geothermal field that supports geysers, heated mineral pools, and a long-running geothermal power plant. This area is part of the Central American Volcanic Arc, a chain of volcanoes stretching over 1,000 kilometers along the Pacific coast from Guatemala to Panama.
The Santa Ana volcano, at 2,381 meters above sea level, is the country’s tallest volcano. It has a history of small to moderate explosive eruptions since the 16th century, including a significant event in 2005 that produced a gas and ash plume and lahars. Next to Santa Ana, the Izalco volcano formed in 1770 on its southern flank and became known for frequent Strombolian eruptions and lava fountains until its last activity in 1966. Its persistent glow earned it the nickname 'Lighthouse of the Pacific'.
The Apaneca Range includes forested stratovolcanoes without recorded Holocene eruptions but shows continuous geothermal activity with fumaroles, hot springs, and steam vents. The region has experienced steam explosions, notably a deadly blast near Laguna Verde in 1990 and a 2025 steam eruption near a popular hot springs site that caused evacuations and infrastructure damage.
Geothermal energy from this volcanic activity has been harnessed by the Ahuachapán Geothermal Power Plant, operating since 1975. It uses groundwater heated to about 250 degrees Celsius and local fault lines to generate electricity, producing up to 40 percent of the country’s power by the early 1980s. Some scholars have noted this energy production coincided with a period of civil unrest and increased local population.