The Stack in Porto di Levante, around 70 metres high, is what remains of a volcanic structure in the north-east part of the Caldera of the Fossa, between here and Vulcanello.
In the second half of 1800, before the eruption of 1888-1890, the Stack was known as “the Factory” because of the intense sulphur and alum mining activity here.
The “entrepreneur” at the time of the Bourbons was General Nunziante, who was succeeded by the Stevenson family from Glasgow, Scotland. For the merits achieved in battles against Napoleon, Ferdinand I, King of the Two Sicilies, gave the island of Vulcano to Nunziante as a fief.
The general employed around fifty workers from Lipari and Salina, who lived in the small grottoes adjacent to the alum cave, a very large artificial cave, 34 metres deep with four openings, dug at the foot of the north face of the Great Stack (Faraglione Grande).
Aluminous salt was extracted from it daily, by detaching it from the sides of the cave, within which sulphurous water boiled.
In the Great Stack there are around thirty cavities.
From here the Small Stack (Faraglione Piccolo) in front can be admired, a large rocky arch, the remainder of another large cave used for alum extraction. In 1878 the heirs of General Nunziante sold their rights to the Stevensons, who bought the island for £8000 and were already working in the pumice industry in Lipari.
