Study area

The river Potenza rises in the central part of the Umbria-Marches Apennine mountains, near the Monte Pennino (1571m). This mountainous interior was subjected to complex orogenic phenomena of subsidence and settling which over the centuries led to the formation of clefts and faults, and the landscape now has a great variety of forms with longitudinal and transverse valleys of alluvial origin in the Apennine range. One of these is the Potenza valley, which like many parallel valleys crosses the Central Italian region Marches from the west-south-west to the east-north-east, in the direction of the generally flat Adriatic coastline. Due to the proximity of the Apennines to the sea, the conformation of the river valleys and the irregular rainfall, the flow of rivers like the Potenza is rather short and of a torrential nature, catchment basins are underdeveloped and the rivers are not navigable. Over its ca. 80 km long course the Potenza corridor crosses first a mountainous Apennine sector with peaks around 1500m. This sector is divided in almost north-south oriented calcareous ridges (Umbria-Marche ridge and Marche ridge) and an intermediate basin. Near Pioraco, the river runs through a narrow gorge and enters this intermediate basin to shape a much broader valley. After crossing the calcareous eastern ridge, the Potenza valley widens up towards the sea, traversing the wide en fertile Apennine foothill area, bordered by intricate systems of fluvial terraces. Some 15 km north of the river mouth, itself situated in the middle of the flat sand coast, lies the Monte Conero (572 m), an isolated massif rising on the Adriatic coast, composed of calcareous rock, marl and sandstone. The massif is steep and rocky towards the sea but slopes smoothly inland. In ancient times it was covered with thick woods, in perfect harmony with the vegetation and fauna of both Apennines and coast. The mount and its protected natural harbours constituted an important focus of attraction for Greek merchants and settlers, who between the 6th and the 4th centuries BC much frequented the local emporia of Numana and Ancona.

 

  General view on the Lower Potenza Valley

 

This stimulated the Potenza river valley to become one of the most important commercial routes of the Central Italian protohistoric period, partly linking the Adriatic sphere to the Thyrrenian centres in Etruria, Latium and Campania. Not so much the Potenza river itself (called Flosis in Roman times), but its valley remained an important corridor for political, economic and cultural contacts between both sides of the peninsula. From the 3rd century BC onwards Roman influence passed trough it, using a southern branch of the famous Via Flaminia, with a spin off from the main branch at the Apennine site of Nocera Umbra, leading through the Potenza valley towards the port of Ancona. During late Republican and Imperial times several Roman towns developed in or near the valley floor, such as Potentia at the river mouth, Ricina, Trea, Septempeda and Prolaqeum. During the turmoil of the end of the Roman West, the location of the region was again of importance, as it lay within the military contact zones of both Longobards and Byzantines, within the then still flourishing Adriatic sphere.

 

Location of the 3 transect zones of detailed field survey.

Location of the 3 transect zones of detailed field survey.

 

Climatologic conditions, such as temperature, winds, intensity and distribution of precipitations, vary considerably throughout the Potenza valley region, depending on the lie of the mountains, exposure to air currents and the marked differences in altitude of the coastal belt and inland mountains and between valley floors and the peaks. Along the coast the climate is mainly maritime with a limited temperature range and little rainfall; towards the interior, the temperature range increases as do precipitations, reaching as much as 2000 mm/year in some limited mountainous areas. Snow is frequent in winter, mostly inland, while the rainiest seasons are generally spring and autumn. Positive elements for the study of acculturation in a region as the Potenza valley are a/o. the geographic unity, the presence of a river with sea mouth, the passage of important Roman roads, the attested presence of Roman colonies and towns, the vicinity of an old Greek emporion, indications for Roman centuriation and villa systems and the important but ill-known pre-Roman occupation of the Piceni. Geo-archaeological assets are the micro-diversity of the landscape, good cartographic material, good visibility for survey and information from earlier work in the area. Historically important are the good old-toponymic info and the available early written sources and maps.