It is midnight on September 16, 2017, 60 kilometers off the coast of Bulgaria and 2 kilometers below the surface of the Black Sea. A remotely operated vehicle surveys the seafloor, transmitting post to researchers above.
Suddenly, he sees another ghostly vessel in the gloom.
But it is a sign of another era. It is undoubtedly an ancient shipwreck, but its mast, rowing benches, and some of its upper deck are remarkably well preserved.
It may be an ancient Roman ship, but it doesn't look quite the same. In particular, its scalloped rudder blade closely resembles those depicted on an even older Greek vase.
To get a definitive answer, the research team takes three samples from the wreckage and radiocarbon dating confirms its ancient origin. The ship is dated between 350 and 410 BC. In fact, it is the oldest intact shipwreck ever discovered.
This ancient Greek ship sailed the shores of the Black Sea in Aristotle's time and has since rested in its depths, unseen and undisturbed, for nearly 2,500 years. It was just one of 65 ships discovered by a research team at the bottom of the Black Sea between 2015 and 2017.
And despite the centuries,
they have all survived in remarkable condition. So, why are there so many well-preserved shipwrecks in the Black Sea? In prehistoric times, the land around the Black Sea hosted early human settlements.
Eventually, it became a center of trade, warfare, and empire-building due to its strategic position between the East and West Eurasian civilizations. For thousands of years, it was passed by traders, pirates and warriors.
And with the continued activity of seafaring came inevitable losses. But unlike other bodies of water in the region, the Black Sea is a particularly deep, semi-enclosed basin.
Climate changes typically cause the layers within an existing body of water to mix together, causing the water to become oxygenated. But since the Black Sea receives fresh water from European rivers and salt water from the Mediterranean Sea, it has two distinct layers.
Saltwater flows beneath freshwater,
where it remains permanently, making the Black Sea the world's largest miromictic — or non-mixing — basin.
Oxygen does not reach its lower, saline region, which creates an ideal environment for preservation, and is why the Black Sea has been called "the world's biggest pickle." In other bodies of water, marine organisms decompose material over time.
For example, if ancient Greek ships had sunk in the Mediterranean Sea, there might not be any organic material left today. But in the depths of the Black Sea, only anaerobic bacteria—those that don't need oxygen—can survive.
This is why ancient ships can still be found carrying their original cargo,
their wood carved, and their rigging still assembled. Recent discoveries include an Italian merchant ship from the Middle Ages, probably from the time when Italy had a virtual monopoly on the Black Sea trade.
The Venetian traveler Marco Polo was probably familiar with this type of ship. Although such ships helped modernize Europe, contemporary scholars had never seen such a complete example before.
And it was largely intact—a ship's boat still lying on its deck, though some seven centuries had passed. Many of the 65 ships that were recently uncovered retain their original form.
But while the forces of degradation are very low in the depths of the Black Sea, anaerobic bacteria slowly degrade the organic material.
When researchers lifted a slab from the ancient Greek wreck for dating,
it broke under its own weight. Although the ships are exceptionally well preserved, they are also fragile.
This makes it impossible to bring them to a constant level. Scientists can carefully remove selected objects from the wreckage and study them.
But the sunken ships will remain safe where they are, perhaps among thousands of others—deep below us, at the bottom of the Black Sea, suspended in time.
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