Schichtvulkan 5321 m / 17,457 ft
Kolumbien, 4.9°N / -75.32°W
Eruption-Liste: 2015-21 (ongoing), 2014-15, 2012-13, 1994 (?), 1985-91, 1984-85, 1916, 1845, 1833?, 1831, 1829, 1828, 1826(?), 1805, 1623, 1595, 1570, 1541(?)
1985 Armero mud flow disaster
Nevado del Ruiz erupted on 13 November 1985. Although the eruption was small, it caused a large mud flow which swept through the town of Armero almost 40 km away from the summit where more than 23,000 people were killed.
The event caused a heated debate because government officials chose to ignore volcanologists'warnings of the imminent danger of the advancing lahar. The eruption itself had been preceded by increased fumarolic, phreatic and seismic activity for a year.
The tragedy was South America's worst and globally the 4th worst volcanic known disaster.
The event was even more tragic, because it the same events had already occurred at least 2 times during earlier eruptions.