杏吧原创

Deep beneath the elaborate mosaic floor of Venice鈥檚聽, archaeologists have discovered two 1300-year-old peach stones. The find may add 180 years to the history of the iconic floating city.

Most of Italy鈥檚 great cities date back to the Romans, but Venice is an exception, says at Colgate University in Hamilton, New York. Although there was a Roman presence on Torcello island in the north of the Venetian lagoon, there are no Roman remains in Venice.

Instead, the history of Venice seems to begin in the 9th Century. Local tradition says the bones of Saint Mark the Evangelist were carried to Venice in AD 828, from Alexandria in Egypt. The earliest Basilica named in Saint Mark鈥檚 honour was built a few years later.

Now, Ammerman and his colleagues think they have evidence for an earlier chapter of the Venetian story. In one of several sediment cores extracted from the soil beneath the modern Basilica 鈥� built in the 11th Century 鈥� they found two peach stones, or pits.

鈥淭his was like hitting the jackpot,鈥� says Ammerman. Peach stones are ideal for carbon dating, because they grow in just one year and contain lots of carbon. 鈥淎nd with two peach pits there鈥檚 the opportunity for replication,鈥� he says. 鈥淚f they give the same dates you鈥檙e really cooking.鈥�

Peachy

Both peach stones did yield a similar age, as did a fragment of elm charcoal found in the same core. All three dated to between AD 650 and 770 鈥� implying they are 180 years older than the earliest Basilica.

That fits with research Ammerman published in 1995. In sediment cores taken near the Basilica, they found聽聽associated with organic material, which they dated to the 7th and 8th centuries.

The new finds give a better sense of what people were doing in the Venetian lagoon during the 7th and 8th centuries. The two peach stones were almost 4.2 metres below the current ground surface. Using聽, the team established that the sediment layer containing the peach stones was perhaps a metre or more below sea level during the 8th Century. The only explanation, says Ammerman, is that the stones were tossed into one of the natural canals that ran through the Venice lagoon before the city was built up.

What鈥檚 more, the sediment surrounding the peach stones also held fragments of ceramics and metal. The entire sediment is clearly human-made, says Ammerman, and it is 80 cm thick in some of the cores.

Ammerman thinks the sediment core is evidence that people were deliberately filling the natural waterways in the lagoon, in a bid to create the solid dry land on which Venice was ultimately built from the 9th Century onwards.

At home in the marsh

It makes sense that people lived in the area before the 9th Century, says at the University of Franche-Comt茅 in Besan莽on, France. 鈥淗uman societies have been living in and around lagoonal areas for thousands of years, because they are hotspots of biodiversity, rich in resources and afford natural protection from the sea,鈥� he says. 鈥淚t is certainly plausible that humans were infilling some of Venice鈥檚 natural canals to make them dry land.鈥�

Marriner agrees that the core seems to hold evidence of ceramics, hinting at a human presence.

It makes sense that the peach stones got into the lagoon through human action, says at the Sapienza University of Rome, who has written about聽. 鈥淎 peach stone is big and heavy enough not to be easily floated in a lagoon,鈥� she says. The stones may have been dropped into the water from boats.

鈥淭here seems to be sufficient evidence for a human presence in the area of San Marco in the 7th and the 8th century,鈥� says art historian Wolfgang Wolters, who聽. A next step might be to look for early buildings beneath Venice, he says.

But such work is difficult in dense cities close to sea level, says Marriner, who has聽.

Political factors add even more complexity, says Ammerman. The coring beneath the Basilica鈥檚 precious mosaic floor, conducted in 2000, was only possible because of the backing of a key figure 鈥� Ettore Vio, the 鈥減roto鈥� or architect of the Basilica.