There are four active volcanoes in Italy, all located in the southern Apennine Mountains. These are the only active volcanoes in all of Europe outside of Greece. Mount Etna on the island of Sicily is the largest active volcano of the four and it is also the highest mountain in Italy south of the Alps. It by far the largest of the volcanoes, being nearly three times the height of the next largest, Mount Vesuvius. Even though it is one of the most active volcanoes in the world and is in an almost constant state of small eruption, Mount Etna is not generally regarded as being particularly dangerous. Thousands of people live on its slopes and in the surrounding areas. The volcanic soils make the ground fertile for agriculture, vineyards and orchards.

Mount Vesuvius lies on the shore of the Bay of Naples. Over centuries, from time to time this volcano will erupt, often with little warning. In the early 19th century a volcano observatory was built on its slopes and ever since then it has been the most observed volcano in the world. Pompeii and Herculaneum are ruined cities near modern Naples that were destroyed during an eruption of Mount Vesuvius in 79 AD. The volcano buried the cities under many feet of ash and they were lost for 1,600 years before their accidental rediscovery. Since then, their excavations have given the world a detailed understanding of the life of a city at the height of the Roman Empire in the 1st century. Today, Pompeii is one of Italy's leading tourist attractions. The excavated town offers a view of Roman lives that were frozen at the moment they were buried, when the top blew off the mountain and hot lava, rock and layers of ash several feet thick landed on top of the cities directly below. The baths, the forum and many houses remain surprisingly well preserved, including their frescoes whose figures throw a great light on how everyday life was lived back then. At the time of the eruption, the town could have had some 20,000 inhabitants, and it was located in an area in which many properous Romans had their vacation villas.

Italy's two other active volcanoes are Stromboli and Vulcano which are found in a group of islands called the Aeolians, off the northern coast of Sicily.