Bagni di Tivoli, Lazio

The modern town of Bagni di Tivoli is situated approximately 20km east of Rome. Over three seasons, in February-March 2007, July 2008 and October 2008 a survey was carried out on two large areas of agricultural land at the northern extent of the town. The fallow and arable fields that comprise this area surround the famous source of a sulphur spring, and two connected sulphur lakes; Lago della Regina and Lago delle Colonnelle.

The work was carried out at the request of Francesco D’Asaro of S.I.A.C.I. s.r.l. in association with the Soprintendenza Archeologica del Lazio, and the landowners, who wished to make use of advanced methodologies for investigating the archaeological potential of the site. The survey was carried out to determine the potential for archaeological remains in advance of development work. As there are substantial surviving Roman building remains above ground, it seemed likely that some material would be preserved beneath ground level. Magnetometer survey was chosen as the best geophysical technique with which to investigate this site.

All three seasons of work successfully identified archaeological features which have the potential to shed light on the ancient activity that focused on these important sulphur springs. Following two weeks of work in the 2007 season, a striking feature was identified in the geophysical survey results. This was a building complex in the far north east of the survey area, close to the southern boundary of the Lago delle Colonnelle sulphur lake. The complex was clearly composed of at least two large buildings, each formed of a number of rooms arranged around a central courtyard. These are on a roughly north-south orientation and from the evidence of their form and the building material visible on the surface should date to the Roman period.

The south west edge of the October 2008 survey area, which lies on the northern boundary of the same spring, revealed further evidence of the Roman complex. In this case a single structure was identified on the same north-south orientation to the other buildings, and which was also formed of a central courtyard surrounded by numerous small rooms. To the north east of the springs the July 2008 survey located a possible road which may have provided access to the Roman settlement. A further structure was located by the October 2008 survey at some distance to the north of the Roman complex. While the results clearly identified a single building divided into three rooms, it was not possible from the plan alone to determine if this structure represented a Roman or later construction.