Visitors were captivated by the eruption of Mount Etna on Sunday (July 7) as the skies over Sicily's Catania were covered in black smoke and ash.

Volcanic activity from Etna's 'Voragine' crater has intensified this week, with vigorous explosions following a four-year dormancy and a guide for Alpine Etna Sud, Giuseppe Amendolia, said he was taking a closer look after the second volcanic convulsion, or paroxysmal activity, in less than 48 hours.

Etna and Stromboli are the most explosive volcanoes, erupting more violently due to minute variations in the chemical composition of their magma.

The 3,330-meter-high volcano Mount Etna, Europe's tallest active volcano, is believed to have the longest documented history of eruptions amongst all volcanoes, with records dating back to as early as 425 B.C.