Discovery of ancient Roman "highway" reveals geomorphic changes in karst environments during historic times

Abstract

Sinkholes are a well-known geologic hazard but their past occurrence, useful for subsidence risk prediction, is difficult to define, especially for ancient historic times. Consequently, our knowledge about Holocene carbonate landscapes is often limited. A multidisciplinary study of Trieste Karst (Italy), close to early Roman military fortifications, led to the identification of possible ancient road tracks, cut by at least one sinkhole. Electrical Resistivity Tomography through the sinkhole has suggested the presence of a cave below its bottom, possibly responsible of the sinkhole formation, while Ground Penetrating Radar has detected no tectonic disturbances underneath the tracks. Additionally, archaeological surveys led to the discovery of over 200 Roman shoe hobnails within or close to the investigated route. According to these data, the tracks are interpreted as the remains of a main Roman road, whose itinerary has been reconstructed for more than 4 km together with other elements of ancient landscape. Our results provide the first known evidence of a Roman main road swallowed by sinkholes and suggest that Holocene karst landscapes could be much different from what previously believed. In fact, sinkholes visible nowadays in the investigated region could have been flat areas filled by sediments up to the Roman time.

Geo-archaeology of the Grozzana area (N–E Italy)

“…Data have been processed and analyzed following the methodology developed in other areas of Trieste Karst and described in previous contributions (Bernardini, 2019;Bernardini et al, 2015Bernardini et al, , 2018aBernardini et al, , 2018bVinci & Bernardini, 2017). All recognized features were systematically checked on the ground to verify the state of conservation and the building technique of the structures and to identify possible stratigraphic relations with other structures and archaeological finds scatters.…”

“…Traces of a large ancient structure of about 1 ha assigned to the Roman period for its shape and orientation (Auriemma & Karinja, 2007;Bernardini et al, 2018a). Some of the wall structures, recognizable on the field as modest ridges of few decimetres high, are covered by modern dry walls recorded in the FCM (Figures 2 and 4).…”

“…Two main clavicula-shaped entrances have been recognized, respectively located on the northern and on the eastern side of the larger structure, of which the latter was not published in previous contributions. Archaeological surface and metal detector surveys within and in the surroundings of the camp allowed to collect tens of Roman shoe hobnails mostly dated back to the late Republican period, amphorae and pottery fragments (Bernardini, 2019;Bernardini et al, 2015Bernardini et al, , 2018a.…”

“…In recent years, the extensive analysis of remote-sensed data and systematic fieldwork carried out in the Trieste Karst (N-E Italy) have revealed a complex palimpsest of archaeological landscapes that was largely unknown (Bernardini et al, 2013(Bernardini et al, , 2015(Bernardini et al, , 2018a(Bernardini et al, , 2018bVinci & Bernardini, 2017;Bernardini, 2019). In this research, a crucial role has been played by the extensive application of Airborne laser scanning data (ALS) which has become of paramount importance to detect either archaeological or geomorphological features in forested areas.…”

HumanOS: an open source nomadic software database for physical anthropology and archaeology

“…In archaeology, techniques used for data acquisition, have evolved considerably since the end of the last century because of the digital revolution. From the excavation book associated with drawings or engravings, some archaeologists today practice the site detection with satellite imagery (Baeye et al, 2016;Elfadaly & Lasaponara, 2019;Lin et al, 2014), ground-penetrating radar (GPR) (Conyers et al, 2019) or electrical resistivity tomography (ERT) (Bernardini et al, 2018), the 3D digitization of the existing (lidar, photogrammetry and Computed Tomography (CT) scan) (Davies et al, 2012;Leierer et al, 2019;Santos et al, 2017;Waagen, 2019) and hypothetical reconstruction (Ferrari & Quarta, 2019;Rua & Alvito, 2011;Themistocleous, 2017). Rescue archaeology generates a large volume of data that should be homogenized to promote their sharing and synthesis (Altschul et al, 2017;Kintigh et al, 2014).…”