Archaeologists uncover lost island near Koper

Archaeologists have made a groundbreaking discovery near the coastal town of Koper, Slovenia, revealing that what is now known as Sermin Hill was once an island in prehistoric times. During the construction of a new arterial road on the outskirts of Koper, excavations led by the firm Arhej uncovered the 2,000-year-old riverbed of the Rižana River. These findings suggest that the area was significantly different in the past, with the hill surrounded by water rather than land. The excavation, which began in 2020 and has largely concluded, has provided valuable insights into the region’s history and early human activity. The project, spanning multiple phases, focused on the southeastern and southwestern base of Sermin Hill. Lead archaeologist Ana Plestenjak noted that the site shows signs of continuous human settlement dating back to the Neolithic period. Excavations along the narrow strip of the new road revealed extensive economic infrastructure, indicating that the area was actively used by communities over millennia. While Bronze and Iron Age settlements were identified, the landscape underwent major changes after the arrival of the Romans in the 2nd century BC. This shift marked a turning point in the region’s development, leading to the construction of roads, the establishment of a Roman villa, and the transformation of the surrounding environment. Among the key findings were six simple roads built from stone rubble and topped with fine sand. These roads stretched up to 400 metres and connected various parts of the hill, suggesting a well-planned layout designed to facilitate movement and trade. In addition to the roads, teams discovered drainage ditches, Roman retaining walls, and a partially explored Roman villa. Several graves dating from the 1st to the 5th centuries AD were also uncovered, offering a glimpse into burial practices and social structures of the time. A particularly notable discovery was the ancient riverbed of the Rižana River, located deep beneath modern sea levels. This find, situated on the western edge of the site, confirmed that the Rižana once flowed around both the eastern and western sides of Sermin Hill, effectively transforming the hill into an island. According to Plestenjak, the Romans later attempted to control the river’s course by reinforcing its banks with stone. The depth of the excavations, up to 2.5 metres below current sea level, suggests that the Roman coastline was approximately two metres lower than it is today. This information provides crucial data on historical environmental shifts and human adaptation strategies. Despite the significance of these findings, the excavation faced considerable challenges due to the marshy terrain and high groundwater levels. As a result, the digging teams were unable to reach the sea directly. Nevertheless, they managed to recover a wealth of Roman artefacts, including pottery, roof tiles, and various bronze objects. These items are currently being transferred to the Koper Regional Museum for preservation and further study. The ongoing efforts of the archaeologists continue to shed light on the complex interplay between human activity and environmental change in this part of Slovenia.