Galeras (Colombia)

Galeras, a highly active stratovolcano in southern Colombia, is one of South America's most dangerous volcanoes. Rising just 9 km from the city of Pasto (population 450,000), its frequent eruptions since the 1990s—including a deadly 1993 explosion that killed six scientists—highlight its unpredictable nature. Classified as a Decade Volcano due to its high-risk profile, Galeras produces ash plumes, lava flows, and pyroclastic surges. Despite constant monitoring, its proximity to densely populated areas makes it a persistent threat, blending scientific intrigue with human vulnerability.