Uninhabited natural paradise lies in the Gulf of Gaeta between Rome and Naples

S. Stefano island, the smallest of the Pontine Islands off the mainland between Rome and Naples, is on the market. The tiny circular island measures about 400m in diameter and lies two km east of the larger Ventotene.

The island's anonymous owner has put it on the market for an unspecified amount, according to real estate agency Remax which is handling the sale. It is not the first time the island has been put up for sale; in 2005 it was offered for an asking price of €20 million but failed to find a buyer.

The current sale comprises approximately 25 hectares, out of the island's total 28 hectares. The remaining three hectares – which stay in the hands of the Agenzia del Demanio, the Italian public body responsible for the management of state-owned heritage properties – contain the long-abandoned former prison which was opened by the House of Bourbon in 1795 but has been disused since 1965.

Originally built for 600 inmates, the jail's 99 cells contained 800 prisoners in 1817. Surrounded by sheer cliffs, no prisoner ever managed to escape from the island. Among those sentenced to penal servitude there was the anarchist Gaetano Bresci who assassinated King Umberto I in 1900, while during the Mussolini era the prison housed anti-fascist activist Sandro Pertini, who went on to serve as President of Italy from 1978-1985.

With the exception of day-visits from occasional tourists, S. Stefano has been uninhabited since the closure of the prison. Described as “an unspoilt natural paradise”, the island is part of a marine protected area and is subject to strict environmental and landscape constraints – applicable to both the state and the island's owner – meaning it can never become a resort. The new owner will not be permitted to construct new buildings or add to the existing structures on the land for sale, which amount to some 2,000 sqm in total.

The Remax agency boasts that the island's "natural views, splendid sea and a seabed rich in fish and marine flora constitute a unique setting for those who love the sea and underwater sports." The island does not have a water network but there are numerous tanks for rainwater collection, and solar panels for energy.

In ancient Roman times, Emperor Augustus's daughter Julia lived on the island, and the remains of a Roman settlement are still visible, including the so-called Villa Giulia and the Giulia pool carved into the sea rocks with a series of chiselled-out steps leading down to it.

Although S. Stefano is in a much higher price bracket, Remax will be hoping for a repeat of the recent successful sale of another Italian island off northern Sardinia to a private buyer. New Zealand businessman Michael Harte paid just under €3 million at auction for the pristine Budelli Island, an Italian national park with a famously pink beach, on which Italy's environment ministry retains the "right of pre-emption" to buy back within 90 days for the same price paid at auction.

However no such condition will affect whoever purchases S. Stefano.

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