Sicilia (Sicily) is the largest island in the Mediterranean Sea and one of the 20 regions of Italy. It is separated from the Italian Peninsula by the narrow Strait of Messina, about 3 km wide in the north, and about 16 km wide in the south. Its most prominent landmark is Mount Etna (3,329 m asl), one of the tallest active volcanoes in Europe. It is also the most active volcano in the world and produces lots of lava tubes, several may be visited.
Sicily is located at the collision of the Eurasian and the African plates. Since the late Oligocene, the African plate has been subducted in a westward-dipping subduction zone. It has four major tectonic units, the Hyblean foreland, the Gela foredeep, the Apenninic-Maghrebian orogen, and the Calabrian Arc. The Hyblean foreland is the southeastern part of the island is a northward-dipping monocline with a rather high dip of 16–18°. It consists of limestones and other carbonatic rocks, like turbidites, chalk, and calcarenite. The younger limestones are interbedded with basalt. The Gela foredeep is a series of Late Miocene-Pleistocene sediments, including marly limestones, Messinian evaporites and sandy clays. It is located along the southern coast of Sicily. The Apenninic-Maghrebian orogen is the central and western part of Sicily. It is the fold and thrust belt of the subduction system between African and European plate. The rocks consist of a stack of detached nappes composed mostly of Mesozoic carbonates. All three units are karstified.
The fourth unit is completely different. The Calabrian crystalline basement in the northeastern part of Sicily is a part of the Calabrian Arc. Paleozoic igneous and metamorphic basement rocks with the active stratovolcano Mount Etna. There is no karstification but numerous rather young lava tubes.
Sicily was known for sulfur mining which dominated the world market in the first half of the 20th century. Sulfur was one of Sicily’s most important mineral resources. It is no longer exploited. The mines are concentrated on the chalky-sulfur plateau between the provinces of Caltanissetta, Enna and Agrigento. There were actually several hundred sulfur mines. There are eight mining museums in Sicily dedicated to sulfur mining, and the Museum of Mineralogy at the University of Rome "La Sapienza" has an impressive collection of sulfur minerals.
Gole dell’Alcantara
Ddieri di Baulì
Spiaggia Bue Marino
Grotta del Cammello
Antiche Grotte del Caricatore
Grotta Entella
Parco Minerario Floristella Grottacalda
Grotta del Gelo
Grotta del Genovese
Grotta dei Lamponi
Grotta Mangiapane
Grotta delle Palombe
L’Eremo di S. Corrado Fuori le Mura
Chiesa Rupestre di San Nicolò Inferiore
Grotta di Sant’Angelo Muxaro
Grotta di Santa Ninfa
Grotte di Sciacca
Lago Sfondato
Grotta della Sibilla di Marsala
Museo Arte Contemporanea Sotto Sale
Castello di Sperlinga
Grotta delle Trabacche
Museo della Miniera Trabia Tallarita
Grotta dei Tre Livelli
Cava d’Ispica
Castello Sicano
Parco archeologico di Cava d’Ispica
Cavallo d’Ispica
Parco Archaeologico Forza
Chiesa Rupestre di S. Nicola
Palermo
Grotta dei Beati Paoli
Catacombe dei Cappuccini
Grotta di Carburangeli
Grotta Conza
Sorgente del Gabriele
Grotta dei Puntali
Qanat Gesuitico Alto
Qanat Gesuitico Basso
Qanat di Palermo
Santuario di Santa Rosalia
Siracusa
Fonte Aretusa
Fonte Ciane
Maria SS. Addolorata a Grottasanta
Latomie
Grotta Monello
Ipogeo di Piazza Duomo
Chiesa di San Filippo Apostolo
Catacombe di San Giovanni
Catacomba di Santa Lucia
Pantelleria Island
Bagno Asciutto Grotta Di Benikulá
Grotta dei Briganti
Arco dell’Elefante
Grotta del Freddo
Grotta di Sataría