Nevado del Ruiz Volcano

Neva'do del Rui's volcano, located in the Colombian departments of Caldas and Tolima, 40 km north of the city of Manizales, is the highest active volcano of the Andean volcanic belt and has been active for about 2 million years.

Nevado del Ruiz is a large stratovolcano (layered volcano), has a conical shape and is composed of many layers of hardened lava, tephra and volcanic ash.

The modern volcanic cone was formed during the modern period, which began about 150 thousand years ago, and unites five lava domes that cover an area of over 200 square kilometers. On the large top of the mountain is the Arenas crater with a diameter of about 1 kilometer and a depth of 240 meters.

The summit of Nevado del Ruiz is covered with glaciers that have formed over many thousands of years, but have retreated significantly since the last glacial maximum. The first ascent was made in 1936.

The volcano is characterized by mud flows - lahars. Its relatively small eruption in 1985, after a 150-year period of inactivity, caused a huge lahar that almost completely destroyed and cut off from the outside world the town of Armero and killed 23,000 of its inhabitants. It is now believed that up to 500,000 residents of the surrounding areas live under the threat of the emergence of new lahars.