Los Nevados

Declared in 1974, it protects a chain of snow-capped volcanoes rising straight above Colombia's coffee-growing region. On 13 November 1985 a relatively moderate eruption of the Nevado del Ruiz melted part of its ice cap, generating a lahar — a volcanic mudflow — that buried the town of Armero entirely, killing more than 23,000 people in one of the worst volcanic disasters anywhere in the world in the 20th century, a tragedy still studied as an example of early warning systems failing. The park also holds extensive stands of frailejón, an extremely slow-growing plant endemic to the Andean páramo.