This massive volcano complex towers more than 3,500 metres above the Pacific coastal plain to the south and 2,000 metres above the Guatemalan Highlands to the north. The volcano complex comprises remnants of multiple eruptive centers, which periodically have collapsed to form huge debris avalanches. The largest of these avalanches extended more than 50 kilometres from its source and covered more than 300 square kilometres. Contrary to its neighbor, Volcán de Fuego, it has been dormant for the last six hundred years.