The island, located in the north-west of Sardinia, brings the National Park of Asinara, whose area is encompassed among Punta Scolondri, Punta dello Scorno, Punta Salippi and Punta Sabina.
The island has a surface of 51,9 square kilometers, a length of 17,4 km and a width which ranges from 290 meters of Cala di Sgombro to 6.4 km of the northern part; it has a coastal development of 110 km and the highest altitude of 408 metres (Punta della Scomunica). The territory is entirely state property.
The marine and underwater island environment is a protected natural area, with an extension of 10.732 hectares over the sea. From a geological point of view, the Asinara is part of the Nurra, on the north-east of Sardinia, made up by more than 80% of granolithic and micacistes rock which characterize the island landscape together with the vegetation of wood and garrigues. Among the metamorphic rocks, great interest is attached to rare black anfiboliti erciniche that are 950 million years old, being the oldest rocks in Italy.
The Asinara is formed by four mountain agglomerations that are surrounded and linked by a narrow and flat coastal belt. The west coast, with very deep bottoms, is steep and rocky, whipped by the winds of the fourth quadrant and almost inaccessible from the sea (phalesies can sometime overpass 200 m) ; the west coast, flat or uneven, climbs down towards the bay of Asinara and presents the typical rias morphology with nook and sandy shores (Fornelli, Sant'Andrea, Cala Arena, La Reale) and related ponds behind the dunes.
The first human traces can be found in the prehistory with the "domus de ianas" (sprites' houses) built inside soft lime stone, unique in the island, by Campu Perdu. For its central position in the Mediterranean, Asinara was already known and enjoyed by Phoenicians, Greeks and Romans; in the middle age monks from Camaldoli settled in there devoting themselves to agriculture; more recently,
In late ‘700, shepherds from Sardinia and Liguria colonized the island till 1885 when all the 500 inhabitants had to move away to let the isle becoming a penal colony and a quarantine station (as decided by King Umberto di Savoia).
During the great War it was a concentration camp for many thousands of austro-hungaric soldiers, and 5000 soldiers died on the island and were buried in a dedicated charnel house. In the 70's it become a high security prison for convicts for organized crimes, also imprisoning the most dangerous criminals of red brigades, Sardinia anonymous and mafia.
An history definitely marked by human presence and by a strong isolation too, which allowed to safeguard the place while avoiding feasible ventures or tourism settlement developments, elsewhere characterizing the territory.