Located on the island's east coast, Mount Etna is perhaps Sicily's best-known geological feature encompassing nearly 48,000 acres within Etna National Park. A UNESCO World Heritage Site and the highest volcano in Europe known for its frequent activity (it's erupted as recently as spring 2019), Mount Etna hosts hikers in the summer months and skiers during the winter. It is a great stop for nature lovers. In addition to the volcano itself, there are several interesting geological features like caves, grottos and even a glacier. The Etna Park Visitor Center offers naturalist-guided tours that depart from the center.
Visitors recommend taking the Circumetnea Railway nearly 130-mile ride around the volcano, but advise you may have to pay to park and suggest bringing layers of clothes for changing temperatures. You can also opt for a cable car operated by Funivia Dell'Etna followed by a bus ride to reach the upper crater area of the volcano. The south area with cable car access, Rifugio Sapienza, offers free parking. You can also hike at any point, but certain elevations require you to have a guide.