This little island, lying about 37 kilometres off the coast of Livorno, is especially important from the naturalist viewpoint, for its geological, botanical and zoological features. Included in the Tuscan Archipelago National Park, it is at present the site of a penal colony established here in 1869.

The island was also the site of an important astronomical observation conducted in the second half of the 17th century. On June 16, 1666 Donato Rossetti, a canon from Livorno, who had studied with Giovanni Alfonso Borelli and Lorenzo Bellini, observed with a terrestrial telescope, from the highest peak on the island, a "horizontal" eclipse of the Moon. This is a rare phenomenon in which the setting Sun and the eclipsed Moon appear contemporaneously above the horizon. His observations, made on behalf of the Accademia del Cimento, were recorded in a drawing, found today at the National Central Library of Florence.