Mount Vesuvius is a composite stratovolcano, more specifically a somma–stratovolcano (a stratovolcano that has grown within the caldera of an older volcano).

Volcano type

• Geologists classify Vesuvius as a stratovolcano because it is built from many layers of lava flows, ash, pumice, and other volcanic debris.

• It is also described as a somma–stratovolcano since the modern cone sits inside the older Monte Somma caldera, so the full complex is often called Somma–Vesuvius.