Mount Karthala or Karthola is an active volcano and the highest point of the Comoros at above sea level. It is the southernmost and larger of the two shield volcanoes forming Grande Comore island, the largest island in the nation of Comoros. The Karthala volcano is very active, having erupted more than 20 times since the 19th century. Frequent eruptions have shaped the volcano’s 3 km by 4 km summit caldera, but the island has largely escaped broad destruction. Eruptions on April 17, 2005 and May 29, 2006 ended a period of quiet.