Cerro Negro de Mayasquer is a volcano on the border of Colombia and Ecuador. It lies 3 km north-west of the volcano Chiles, and the two peaks are considered part of the same Chiles-Cerro Negro volcanic complex. These volcanoes, together with Cumbal are andesitic in rock type. A 1936 eruption reported by the Colombian government agency INGEOMINAS may have been from the Ecuadorean volcano Reventador, otherwise the volcano has not erupted for around 160,000 years.