ROME - The good news is that UNESCO has just recognized five more Italian sites as part of the world's cultural heritage - that is, they meet the United Nations criteria because they are of universal cultural interest, are unique and are irreplaceable. The additions bring the number of  world heritage sites in Italy to 47, more than in any other country. Several dozen other Italian sites are also under consideration for future recognition, moreover. 

There is also bad news: that Florentine Mayor Matteo Renzi has blocked engineer Maurizio Seracini's thirty-year search for a mysterious Leonardo Da Vinci masterpiece fresco, believed to exist - at least in part - on a wall in the 14th century town hall in Florence by.

But first, UNESCO. The newest additions to the list of magnificent Italian cultural treasures begin with a series of ten buildings dating from the Arab-Norman period in Palermo. The others are the volcano Mount Etna; the hillside vineyards which produce the sparkling prosecco of Conegliano and Valdobbiadene; the National Park of the Sila and - of particular interest - the 1926 Olivetti "Borgo" of six workers' houses at Ivrea.  For a fascinating tour of these newly listed heritage sites, take the Internet photo tour called "Pedalando per i siti dell'Unesco," (Cycling through the UNESCO sites), a series of nineteen stunning photos by Alessandro Cristofoletti. See here [2].

As a study by the Italian national statistics agency ISTAT, based on UNESCO data, showed, Italy placed just ahead of Spain in the number of world heritage sites, followed in this order by France, Germany, China, Mexico and the UK. Official UNESCO statistics released earlier this year showed that, of a world total of 936 heritage sites (725 of them considered "cultural," 183 "environmental," and 28 "mixed"), Italy had 44. Nevertheless, as culture critic cum blogger Federico Giannini has pointed out, an announcer of RAI TV's 2d channel nevertheless recently repeated the old and erroneous saw of Italy having "half" of the world's cultural heritage. 

The number is huge at any rate, and ownership of such riches is no easy responsibility, as the search for the lost Leonardo in Florence illustrates. Around the year 1503 Leonardo Da Vinci painted a wall scene [3] in the great Hall of the Five Hundred inside the 14th century Palazzo Vecchio of Florence showing the Battle of Anghiari, in which the Florentines defeated the forces of Milan. Considered by art critics to be among Leonardo's greatest masterpieces, it seems to have vanished even before it was finished, for still unknown reasons. Later, the wall was again painted, but this time by Giorgio Vasari, who covered the wall with another boastful battle scene, this one celebrating a Florentine victory at Marciano della Chiana. 

The commission to Leonardo was granted by the Secretariate of the Florentine Republic, in the presence of Machiavelli; if not exactly a friend of Leonardo, the author of The Prince had a personality which intrigued Leonardo, and the two men are known to have spent time together. What remains today of Leonardo's painting - a few stunning preparatory sketches showing men on horseback in a battle to the death, and a drawing made by Peter Paul Rubens a century after Leonardo painted the wall - suggest that it was an extraordinary work of art.

But if so, why was work on it left incomplete? One theory has been advanced by art historian Roberto Esposito, writing this week in the daily La Repubblica [4]. According to Esposito, what made Leonardo's battle scene so exceptional was his analysis of the horses in the violence of the battle. Typically horses in battle scene represented the ultimate bestiality, but for Leonardo it was the men in battle reduced to bestiality, taking with them the horses. The few surviving preliminary drawings show "pure violence...enigmatic and extreme," to quote Esposito; was this all too dark vision what made Leonardo halt work on the fresco? 

Beginning in the Seventies engineer Maurizio Seracini, who lives and works between Florence and San Diego, California, has been conducting a sophisticated search for traces of the lost Leonardo. In an interview some time ago Seracini told me that he believed that Vasari left what he could of the painting in a niche behind the Vasari-era wall.

Hoping to rediscover the lost Leonardo, or at least a piece of the original, Seracini has utilized ultra high-tech tools to make a series of surgery-style keyhole explorations that, while only minimally damaging the Vasari, theoretically peek through the Vasari surface so as to see what lies below. Seracini's probes have generated worldwide interest, not surprisingly, and the U.S. National Geographic has been filming his efforts.

Last November, Seracini reported in a press conference that he had found, behind the Vasari, traces of a color that only Leonardo is believed to have used at that time. Most importantly, the color traces prove that a painting does in fact exist in a space behind the Vasari wall, as if left there intentionally by the later artist.

But poking keyholes into the Vasari did not suit everyone, and a prosecutor opened an inquiry - subsequently dropped - into possible damage. The Florentine administration was nevertheless put on the defensive. "My administration has made culture the keystone of our mandate," Mayor Renzi wrote Minister Ornaghi earlier this year. "The search for the Battle of Anghiari for us falls within the logic of investing in culture as a part of our city's identity."

Nevertheless, last month the cultural overseer for Florence, Cristina Acidini, speaking on behalf of Italian Culture Minister Lorenzo Ornaghi, wrote Renzi that it would violate Italian law for Seracini to continue hunting for the lost Leonardo because of the risk of damage to the Vasari fresco. A disheartened Mayor Renzi had no choice but to accept the government's decision. 

Renzi's response, in a letter to Ornaghi: "For almost five hundred years the Florentine community has been discussing the possibility that Leonardo da Vinci's masterpiece The Battle of Anghiari is hidden in the Hall of the 500 behind a fresco by Vasari....  If the Minister fears authorizing what is constantly authorized all over the world, we will wait until a new government comes into office. We may have to wait a few months but we will see this research through to the end." 

Professor Seracini's work is backed by the City of Florence, the University of California at San Diego, private sponsors, most recently coordinated by National Geographic [5].