Cotopaxi is a stratovolcano in the Andes Mountains, about south of Quito, Ecuador, South America. It is the second highest summit in the country, reaching a height of . Some consider it the world's highest active volcano. Others give this status to the much higher Llullaillaco, which most recently erupted in 1877 and is one of Ecuador's most active volcanoes. Since 1738, Cotopaxi has erupted more than 50 times, resulting in the creation of numerous valleys formed by lahars (mudflows) around the volcano.