by Marco Valenti, Università degli Studi di Siena

Poggio Imperiale is a flattened and elongated hill 200m above sea level that extends over almost 12 hectares. It is situated to the immediate west of the centre of Poggibonsi, local council head office, and one of the main economic centres of the region.

The site is characterised by its IV century fortifications requested by Lorenzo di Medici to Giuliano da Sangallo and is part of an ancient area of inhabitation that includes the Franciscan convent of San Lucchese and the castle of Badia già Marturi, whose current appearance is the fruit of radical transformations in the XIX century.

The fortifications represent the real historic centre of Poggibonsi: between 1155 and 1270 a castle and then the urban nucleus of Podium Bonzi arose and then in 1313 it was selected, by the emperor Arrigo VII, as the site of the new city, Monte Imperiale that was destroyed after only five months. The site is of particular interest to the area’s history that views the Podium Bonzi as representative of a very particular period. In 1992 the hill was at the centre of a systematic study carried out in the area by the department of Mediaeval Archaeology of the University of Siena.

Following a preliminary investigation to comprehend the true quantity of archaeological deposits located on the site, a long term excavation began in 1993 (that continues today): this revealed signs of human habitation dating back long before the period that had previously been imagined. Using written sources, the archaeologists demonstrated that the history of settlement on the hill had begun at least seven centuries before. The archaeological sequence soon discovered remains from a village dating back to the V century, followed by a medieval village of huts that dated back to the mid X century and evidence was revealed that showed the existence of an urban nucleus of 4000-5000 inhabitants for approximately 115 years, founded by the Count Guido Guerra dei Guidi, prior to the construction of the Medici fortress,

Poggio Imperiale consists of an area extremely rich in both monuments and archaeology that, from September 2003 has been at the centre of the archaeological and technological park of Poggibonsi that involved the Department of Archaeology and History of Art of the University of Siena, the council of Poggibonsi and the Monte dei Paschi di Siena Foundation as part of the project “archaeology of Medieval landscapes”.