The Prehistoric Settlement beneath the Waters of Sozopol
After more than 15 years without active research, in 2020 a team from the Centre for Underwater Archaeology resumed fieldwork in the waters of the Old Fishing Harbour in Sozopol. The underwater rescue excavations were carried out in connection with a project by the Municipality of Sozopol for the installation of floating piers. These investigations led to a reassessment of the results from earlier studies conducted in the XX century and initiated the development of a long-term programme for underwater archaeological research in the waters around Sozopol. As the first stage of this programme, excavations were carried out in 2021 in the southern part of Sozopol Harbour, in the so-called “East Sector,” with funding from the Ministry of Culture. These revealed a well-preserved section of a settlement from the end of the Early Bronze Age, which had not been disturbed by previous dredging activities and holds great potential for the comprehensive study of the prehistoric settlements of Sozopol.
Earlier investigations of the submerged prehistoric settlements were carried out from the mid-1980s to the early 1990s in three sectors. Several test trenches (squares) were opened in each sector, where archaeological materials from the Early Bronze Age (early IIIrd millennium BC) and the Late Chalcolithic (late IVth millennium BC) were discovered at depths of approximately -6.5 to -7 metres. A series of underwater excavations were conducted during the 1990s, during which valuable stratigraphic observations were made. These excavations raised new research questions for underwater archaeology in Bulgaria, particularly concerning past changes in Black Sea levels and the study of the so-called “Transitional Period” between the Chalcolithic and the Early Bronze Age along the Western Black Sea coast. In addition to the established methodology of stratigraphic underwater excavation, this period marked the beginning of interdisciplinary research approaches, involving both Bulgarian and international specialists from various scientific fields. Pioneering hydrographic and geophysical surveys with archaeological applications were undertaken, alongside the introduction of computer-based and digital methods, as well as paleoenvironmental and dendrochronological analyses. Over the following decades, this interdisciplinary approach became a hallmark of the Centre’s work.
During the 2021 campaign, two 5×5 metre squares—“Y” and “X”—were excavated. Stratigraphic observations in square “Y” revealed four main layers, which reflect the existence of a harbour in use from the 4th century BC. to the Ottoman period, a prehistoric settlement from the Early Bronze Age, and significant changes in sea level in the region:
Layer I is a surface fill of loose sand mixed with shells and stones, containing a mixture of archaeological materials from the Ottoman period to the Early Bronze Age. It was likely redeposited during dredging in the 1980s.
Layer II is a sandy-silty deposit representing the natural seabed, upon which harbour-related materials from various historical periods were deposited, though without clear stratigraphic succession.
Layer III contains mostly oyster shells and fragments of Early Bronze Age pottery (decorated with impressed dots), burnt plaster, a small flint flake (a core fragment), and stones showing signs of use. The small number of finds suggests this square lies on the periphery of the Early Bronze Age settlement.
Layer IV is a homogeneous layer of fine marine sand with no archaeological materials, likely representing a coastal dune formed when sea level was approximately 5 metres lower than today, at the beginning of the IIIrd millennium BC.
Excavation of square “X” revealed part of the historical harbour that had been disturbed by earlier construction work, likely related to the building of the “Fish Resources” pier. At a depth of about -0.9 metres from the seabed, a layer with well-preserved remains of a settlement from the end of the Early Bronze Age was uncovered. Structural elements of buildings were found—vertically driven wooden posts and horizontally placed wooden beams, some showing signs of burning. Excavations of this Early Bronze Age layer continued in 2022, with the team expecting to uncover remains of an earlier Final Chalcolithic settlement (late IVth millennium BC) beneath it – sectors of which have been identified in other parts of Sozopol’s harbour waters.
