"This is the result of many years of work and two decades of technical meetings," Italy's UNESCO ambassador Maurizio Enrico Luigi Serra.
He said Mount Etna, one of the world's most active volcanos, was "a never-ending source of geological data." Eruptions from the volcano located in north-eastern Sicily have been observed since the Greek and Roman classical era.
China's Xinjiang Tianshan, Mexico's El Pinacate and Gran Desierto de Altar Biosphere Reserve, Kenya's Mount Kenya-Lewa wildlife conservancy and the Namib Sand Sea coastal desert in Namibia were also inscribed in the World Heritage List.
Xinjiang Tianshan includes a part of one of the world's largest mountain ranges. It is home to most of the world's endangered snow leopards.
Tajikistan's National Park in the mountains of the Pamirs, at the centre of the highest mountain ranges on the Eurasian continent, became the country's first World Heritage Site.
India's Hill Forts of Rajasthan and the Wooden Tserkvas in the Carpathian Region between Poland and Ukraine were granted World Heritage status as cultural sites.