Stratovolcanoes are sometimes called " composite volcanoes " because of their composite stratified structure built up from sequential outpourings of erupted materials . They are among the most common types of volcanoes , in contrast to the less common shield volcanoes . Two famous examples of stratovolcanoes are Krakatoa in Indonesia , known for its catastrophic eruption in 1883 and Vesuvius in Italy , whose catastrophic eruption in AD 79 ruined the Roman cities of Pompeii and Herculaneum . Both eruptions claimed thousands of lives . In modern times , Mount Saint Helens and Mount Pinatubo have erupted catastrophically , with fewer deaths
catastrophic eruption in AD 79
Eruption of Mount Vesuvius in 79
Stratovolcano