Together with El Misti, Sabancaya and Ubinas, Coropuna is considered to be one of Peru's most dangerous volcanoes. The presence of an ice cap, and therefore the risk of incandescent volcanic rocks melting that ice, creates a hazard of lahars, or mudflows, such as those that in 1985 killed over 23,000 people at Nevado del Ruiz volcano in Colombia. The risk to life is further increased by Coropuna's steep slopes and by the concentration of people in nearby valleys. The terrain around the volcano has one of the greatest topographic reliefs in the world and a number of towns lie on the floor of the Majes valley, right down to the Pacific Ocean where the district capital Camaná with 20,000 inhabitants is situated. Although there is no evidence of past mudflows of such size, lahars could reach as far as the coast, affecting a number of towns and infrastructure such as roads, antennas and small hydropower plants. According to the 2007 census, 110,481 people lived in the provinces that span Coropuna and lie downstream of it.