6,000-Year-Old Submerged Prehistoric Settlement Reveals Black Sea Level Was 5 Meters Lower 5,000 Years Ago

6,000-Year-Old Submerged Prehistoric Settlement Reveals Black Sea Level Was 5 Meters Lower 5,000 Years Ago

Archaeological materials discovered in 2020 show that the submerged prehistoric settlement near the mouth of the Ropotamo River in Southeast Bulgaria was actually settled 6,000 years ago, in the Chalcolithic. Photo: archaeologist Kalin Dimitrov, via Radio Free Europe

Underwater archaeologists have discovered that a submerged prehistoric settlement near the mouth of the Ropotamo River in Southeast Bulgaria previously thought to be from the Bronze Age was in fact 1,000 years old, going back to the Chalcolithic (Copper Age), and have established that 5,000 years ago, the level of the Black Sea was 5 meters lower than it is today.

Archaeological traces from the submerged prehistoric settlement on the Black Sea coast, near the mouth of the Ropotamo River in Burgas District in Southeast Bulgaria were first stumbled upon in the 1970s.

In 2017-2019, an international archaeological team from the Black Sea MAP project discovered the submerged prehistoric settlement off the coast at the mouth of the Ropotamo River, and judged it to be from the Early Bronze Age.

The latest underwater archaeological expedition there, however, in September 2020, has now shown that the submerged prehistoric settlement on the Black Sea coast near the mouth was inhabited around 1,000 years earlier than previously believed.

Thus, the research of the Center for Underwater Archaeology based in Bulgaria’s Black Sea town of Sozopol has pushed back its dating to the Chalcolithic (Aeneolithic, Copper Age), ca. 4,000 BC, and it is 6,000 years old.

“Our discovery from this year are materials from the Copper Age from the settlement which at the time of its existence was situated entirely on land – since they have been found in a layer which is characteristic of the land environment,” archaeologist Kalin Dimitrov from the Sozopol Center for Underwater Archaeology has told the Bulgarian edition of Radio Free Europe.

Archaeological research so far indicates that the submerged prehistoric settlement near the mouth of the Ropotamo River in Southeast Bulgaria was continuously inhabited.

After its settling in the Chalcolithic 6,000 years ago, as it turns, it was also inhabited during the Bronze Age. And in the 6th century AD, the Iron Age, the period of Ancient Thrace and of the Ancient Greek colonies on today’s Bulgarian Black Sea coast, the site had a sea port.

In 2017, as part of the Black Sea MAP project, which has produced a number of sensational discoveries from the sunken ships in Bulgaria’s Black Sea zone, the research of the prehistoric settlement at the mouth of the Ropotamo River was restarted due to the fact that the site is very well preserved, and has not been damaged by construction.

“Back then, our research between 2018 and 2020 showed that below the layer of the port there are Bronze Age settlement remains, dating back to the transition between the 4th and the 3rd millennium BC, from the very beginning of the Bronze Age on the Bulgarian [Black Sea] coast,” explains Dimitrov who has been the lead archaeologist in the research effort.

The underwater expedition in September 2020, however, have demonstrated that the settlement goes back to ca. 4,000 years BC, and that at the time it was entirely on land.

The newly discovered Chalcolthic materials show that humans lived in the now submerged prehistoric settlement 6,000 years ago, which is some 1,500 years before the construction of the Cheops Pyramid in Ancient Egypt in the 2,600 – 2,500 BC.

Parts of the wooden stilts that the prehistoric people used to support their homes already in the Bronze Age, after the sharp rise of the Black Sea level, can still be seen today. Photo: archaeologist Kalin Dimitrov, via Radio Free Europe

The above footage of Radio Free Europe provided by archaeologist Kalin Dimitrov shows the underwater research of the submerged prehistoric settlement near the mouth of the Ropotamo River. 

The latest findings from the submerged prehistoric settlement at the mouth of the Ropotamo River, however, also reveal information about climate change and the effect on the rise of the sea level.

They show that about 5,000 years ago, that is, ca. 3,000 BC, the level of the Black Sea was about 5 meters lower than it is today.

The Bulgarian archaeologists have established that while during the original settling of the site near the mouth of the Ropotamo River in the Chalcolithic, the prehistoric coastal settlement was entirely on land, the level of the Black Sea rose rapidly, and in the subsequently Bronze Age the inhabitants of the place already had to build their homes above the water, on top of wooden stilts, i.e. they had to live in stilt houses.

Parts of the wooden stilts from the prehistoric stilt homes in question have been found surviving under water testifying to the rapid increase of the level of the Black Sea during the said period.

The archaeologists have also found out more about the Antiquity Era port which existed at the mouth of the Ropotamo River in Southeast Bulgaria.

“This port operated over a very long period of time, almost without interruption, from the 5th century BC until the Modern Era,” Dimitrov says.

“If one looks at the materials from the various ages, it is very easy to notice the periods of prosperity, development, and wealth of this region, as well as the crisis periods, from which there are almost no materials left,” he elaborates.

The Antiquity port in question was the door to the valley of the Ropotamo River, which was a very fertile and rich region at the time.

The researchers believe that the Antiquity port in question was part of the territory controlled by the Ancient Greek colony of Apollonia Pontica, today’s Sozopol.

The Ropotamo port thus followed the rises and declines of Apollonia Pontica itself.

The Sozopol-based Center for Underwater Archaeology of the National Institute and Museum of Archaeology in Sofia is set to keep researching the 6,000-year-old submerged prehistoric settlement at the mouth of the Ropotamo River in Southeast Bulgaria.

There Bulgarian underwater archaeologists have information of only one more similar submerged prehistoric settlement, whose remains are located below the Black Sea level, off the coast from the present-day port of Sozopol.

Learn more about the ancient and medieval history of Bulgaria’s Black Sea city of Sozopol in the Background Infonotes below!

Also check out these other underwater archaeology discoveries and stories from the Black Sea and Bulgaria:

2,400-Year-Old Ancient Greek Ship from Bulgaria’s Black Sea Zone Declared ‘World’s Oldest Intact’ Shipwreck

Archaeologists Discover Perfectly Preserved 2000-Year-Old Roman Ship, 20 Other Shipwrecks in Black Sea Off Bulgaria’s Coast

Pre-Columbian Mediterranean ‘Round’ Ship Discovered for the First Time by Underwater Archaeology Expedition in Bulgaria’s Black Sea Zone

No ‘Biblical Deluge’ but Gradual Ice Age Melting Made Black Sea ‘a Sea’, Archaeologists Find after Underwater Expedition in Bulgaria’s Waters

Emergency Call for Donations to Save ArchaeologyinBulgaria.com amid the Pandemic Fallout

5th Century BC Ancient Greek Shrine Discovered in First Ever Excavations on Tiny St. Peter Island off Bulgaria’s Black Sea Coast near Sozopol

Submerged Ancient Thracian Capital Seuthopolis in Bulgaria’s Koprinka Water Reservoir Could Be ‘Resurfaced’ with US Government Money

Large Sunken Island Existed off Bulgaria’s Black Sea Coast till Middle Ages, According to Roman Era Maps, Geomorphology Research


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Background Infonotes:

The history of the resort town Sozopol (Apollonia Pontica, Sozopolis) on Bulgaria’s Southern Black Sea coast started during the Early Bronze Age, in the 5th millennium BC, as testified by the discoveries of artifacts found in underwater archaeological research, such as dwellings, tools, pottery, and anchors. In the 2nd-1st millennium BC, the area was settled by the Ancient Thracian tribe Scyrmiades who were experienced miners trading with the entire Hellenic world.

An Ancient Greek colony was founded there in 620 BC by Greek colonists from Miletus on Anatolia’s Aegean coast. The colony was first called Anthea but was later renamed to Apollonia in favor of Ancient Greek god Apollo, a patron of the setters who founded the town. It became known as Apollonia Pontica (i.e. of the Black Sea). Since the Late Antiquity, the Black Sea town has also been called Sozopolis.

The Greek colony of Apollonia Pontica emerged as a major commercial and shipping center, especially after the 5th century AD when it became allied with the Odrysian Kingdom, the most powerful state of the Ancient Thracians. As of the end of the 6th century BC, Apollonia Pontica started minting its own coins, with the anchor appearing on them as the symbol of the polis.

Apollonia became engaged in a legendary rivalry with another Ancient Greek colony, Mesembria, today’s Bulgarian resort town of Nessebar, which was founded north of the Bay of Burgas in the 6th century BC by settlers from Megara, a Greek polis located in West Attica. According to some historical accounts, in order to counter Mesembria’s growth, Apollonia Pontica founded its own colony, Anchialos, today’s Pomorie (though other historical sources do not support this sequence of events), which is located right to the south of Mesembria.

Apollonia managed to preserve its independence during the military campaigns of the Ancient Greek kingdom of Macedon under Philip II (r. 359-336 BC), and his son Alexander the Great (r. 336-323 BC). Apollonia, today’s Sozopol, is known to have had a large temple of Greek god Apollo (possibly located on the Sts. Quiricus and Julietta Island, also known as the St. Cyricus Island), with a 12-meter statue of Apollo created by Calamis, a 5th century BC sculptor from Ancient Athens.

In 72 BC, Apollonia Pontica was conquered by Roman general Lucullus who took the Apollo statue to Rome and placed it on the Capitoline Hill. After the adoption of Christianity as the official religion in the Roman Empire, the statue was destroyed.

In the Late Antiquity, Apollonia, also called Sozopolis lost some of its regional center positions to Anchialos, and the nearby Roman colony Deultum (Colonia Flavia Pacis Deultensium). After the division of the Roman Empire into a Western Roman Empire and Eastern Roman Empire (today known as Byzantium) in 395 AD, Apollonia / Sozopolis became part of the latter. Its Late Antiquity fortress walls were built during the reign of Byzantine Emperor Anasthasius (r. 491-518 AD), and the city became a major fortress on the Via Pontica road along the Black Sea coast protecting the European hinterland of Constantinople.

In 812 AD, Sozopol was first conquered for Bulgaria by Khan (or Kanas) Krum, ruler of the First Bulgarian Empire (632/680-1018 AD) in 803-814 AD. In the following centuries of medieval wars between the Bulgarian Empire and the Byzantine Empire, Sozopol changed hands numerous times. The last time it was conquered by the Second Bulgarian Empire (1185-1396 AD) was during the reign of Bulgarian Tsar Todor (Teodor) Svetoslav Terter (r. 1300-1322 AD).

However, in 1366 AD, during the reign of Bulgarian Tsar Ivan Alexander (r. 1331-1371 AD), Sozopol was conquered by Amadeus IV, Count of Savoy from 1343 to 1383 AD, who sold it to Byzantium. During the period of the invasion of the Ottoman Turks at the end of the 14th century and the beginning of the 15th century AD, Sozopol was one of the last free cities in Southeast Europe. It was conquered by the Ottomans in the spring of 1453 AD, two months before the conquest of Constantinople despite the help of naval forces from Venice and Genoa.

In the Late Antiquity and the Middle Ages, Sozopol was a major center of (Early) Christianity with a number of large monasteries such as the St. John the Baptist Monastery on St. Ivan Island off the Sozopol coast where in 2010 Bulgarian archaeologist Prof. Kazimir Popkonstantinov made a major discovery by finding relics of St. John the Baptist; the St. Apostles Monastery; the St. Nikolay (St. Nikolaos or St. Nicholas) the Wonderworker Monastery; the Sts. Quriaqos and Julietta Monastery on the St. Cyricus (St. Kirik) Island, the Holy Mother of God Monastery, the St. Anastasia Monastery.

During the Ottoman period Sozopol was often raided by Cossack pirates. In 1629, all Christian monasteries and churches in the city were burned down by the Ottoman Turks leading it to lose its regional role. In the Russian-Turkish War of 1828-1829, Sozopol was conquered by the navy of the Russian Empire, and was turned into a temporary military base.

After Bulgaria’s National Liberation from the Ottoman Empire in 1878, Sozopol remained a major fishing center. As a result of intergovernmental agreements for exchange of population in the 1920s between the Tsardom of Bulgaria and the Kingdom of Greece, most of the ethnic Greeks still remaining in Sozopol moved to Greece, and were replaced by ethnic Bulgarians from the Bulgarian-populated regions of Northern Greece.

The modern era archaeological excavations of Sozopol were started in 1904 by French archaeologists who later took their finds to The Louvre Museum in Paris, including ancient vases from the beginning of the 2nd millennium BC, the golden laurel wreath of an Ancient Thracian ruler, and a woman’s statue from the 3rd century BC. Important archaeological excavations of Sozopol were carried out between 1946 and 1949 by Bulgarian archaeologist Ivan Venedikov.

The most recent excavations of Sozopol’s Old Town started in 2010. In 2011-2012, Bulgarian archaeologists Tsonya Drazheva and Dimitar Nedev discovered a one-apse church, a basilica, and an Early Christian necropolis. Since 2012, the excavations of Sozopol have been carried out together with French archaeologists.

In 2010, during excavations of the ancient monastery on the St. Ivan (St. John) Island in the Black Sea, off the coast of Sozopol, Bulgarian archaeologist Prof. Kazimir Popkonstantinov discovered a reliquary containing relics of St. John the Baptist. In 1974, the Bulgarian government set up the Old Sozopol Archaeological and Architectural Preserve.

A 2012 National Geographic documentary featuring the discovery of the St. John the Baptist relics in Bulgaria’s Sozopol can be seen here (in English and here in Bulgarian).


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