South America is a continent marked by powerful geological activity—volcanoes, earthquakes, and floods have shaped its history for centuries. One of the most tragic events ever recorded in the region was the eruption of the Nevado del Ruiz volcano in Colombia in 1985, which killed tens of thousands of people and wiped the city of Armero off the map.
Geological Background
Nevado del Ruiz, standing at 5,321 meters (17,457 ft) in the Central Cordillera of the Andes, had long been known for its periodic activity but had been dormant for decades. In the early 1980s, scientists began to detect warning signs—earthquakes, gas emissions, and minor explosions.
Despite the alerts, local authorities failed to implement an effective evacuation plan, and many residents of Armero did not believe a disaster was imminent.
The Eruption and Its Course
On the night of November 13, 1985, at 9:09 p.m., the volcano erupted violently in a phreatomagmatic explosion. The intense heat melted the glacier covering the summit, generating huge lahars—mudflows made of water, ash, and rock.
The lahars rushed down the valleys at speeds of over 40 km/h (25 mph), reaching Armero, located more than 70 kilometers away, within two hours.
The city was buried under meters of mud and debris.
It is estimated that over 23,000 people died, while thousands more were injured or left homeless.
Global Reaction and Aftermath
The Armero tragedy shocked the entire world. Humanitarian aid poured in from dozens of countries, but rescue operations were hampered by destroyed roads, poor communication, and disorganization.
A tragic symbol of the event was Omayra Sánchez, a 13-year-old girl trapped in the ruins of her home for three days. Her courage and suffering, captured by journalists, became a haunting image of human helplessness in the face of nature.
Legacy and Lessons Learned
The eruption of Nevado del Ruiz marked a turning point in Colombia’s approach to natural disaster management. In 1986, the government established the Colombian Geological Service and expanded volcano monitoring systems.
Public education and awareness campaigns were introduced to prepare residents in high-risk areas for possible eruptions.