Montecristo, also Monte Cristo (/ˌmɒntiˈkrɪstoʊ/,[1] Italian: [ˌmonteˈkristo]) and formerly Oglasa (Ancient Greek: Ὠγλάσσα, romanized: Ōglássa), is an island in the Tyrrhenian Sea and part of the Tuscan Archipelago.

The Romans, however, knew it under the name Mons Jovis ("Mount Jupiter"), and erected an altar to Iuppiter Optimus Maximus on the highest mountain, of which some traces remain.

During the imperial age, the Romans opened some quarries to extract granite, perhaps used in the construction of villas on the islands of Giglio, Elba, and Giannutri.

[4] In this period, the Monastery of St. Mamilian was founded; as a result of donations to the Church, its wealth became legendary, and a chapel was built in the St. Mamiliano Cave where the saint had lived in the fifth century.

[5] In 1843, other people arrived with the intention of cultivating the island: young Tyrolean Adolph Franz Obermüller, and after a few months, Frenchman Charles Legrand and his girlfriend.

Montecristo had previously been plundered in 1860 by Italian exiles living in London, who had come to Italy to join up with the Camicie rosse, but were shipwrecked on the island.

[5] Faced with the huge sum of money claimed by the owner to repair the damage, the government thought it better to buy the island, which was still uninhabited.

The would-be agents belonged to a right wing Albanian expatriate organization known as the Bloku Kombetar Independent led by activist Alush Leshanaku, according to Shyqri Bicaku, an Elbasan native, who underwent training; Bicaku was also taught to use a field radio and became so proficient he was hired on to instruct secret agents from Romania to use the radio for their October, 1951 covert parachute drop into Romania's mountains; the Romanians were captured, tried and executed.

[2] In December 2011 it was reported that black rats, present on the island at least since Roman times, have greatly increased in numbers and pose a serious threat to the birds of Montecristo.

[6] Due to the inaccessibility of the terrain, the island was bombed from the air with poison pellets, as had recently been attempted on Giannutri and Sardinia, despite concerns raised by environmental groups that indigenous species of wildlife and the surrounding waters might also be adversely affected.

The island, formed by the heaving of a submarine pluton, has a slightly elliptical shape, and is wholly mountainous, with several rock ledges rising steeply from the sea.

Also interesting are the Montecristo viper (Vipera aspis hugyi, a subspecies also present in southern Italy, and today considered introduced by humans) and Discoglossus sardus, an amphibian found only in a couple of islands in Tuscany and Sardinia.

[10] Montecristo is also a resting place for thousands of migratory birds and is home to large colonies of seabirds (particularly relevant the yelkouan shearwater, as of 2012[update] critically endangered on the island).

[10] Endemic species include the plant Limonium Montis-christi,[10] the invertebrate Oxychilus oglasicola (snail of Monte Cristo), also present on the islet of Scola, near Pianosa,[10] and the reptile Podarcis muralis calabresiae.

Access by sea is possible only at Cala Maestra (where the seabed is sandy) and with an approach course perpendicular to the coast; it is possible to dock at the pier or tie up against a buoy, but dropping anchor is not allowed; there is also a small heliport for emergencies.