Colombia lies at a complex tectonic junction where the Nazca and Caribbean plates converge against the South American Plate. This double interaction fractures the Andes into three separate ranges and generates frequent earthquakes as well as a chain of active volcanoes running through the heart of the country.
The 1985 eruption of Nevado del Ruiz triggered a deadly lahar that buried the town of Armero, killing more than twenty thousand people in one of the world's worst volcanic disasters. Other restless volcanoes include Galeras and Nevado del Huila, while the 1999 Armenia earthquake reminded the coffee region of its persistent seismic risk.