On the turbulent waves of the Stockholm archipelago, four archaeologists prepare to dive into the depths of the Baltic Sea, which is home to exceptionally preserved wrecks.
Their mission: to explore a merchant ship that sank nearly 500 years ago, and verify that it has not been visited by thieves again.
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Faced with an upsurge in cases of archaeological looting in recent years, the team of maritime museums in the Swedish capital asked for reinforcement last spring from the navy, coast guard and police to document the wrecks, monitor them and detect any damage.
That day, Jim Hansson and his team must reach a site with the remains of a 16th-century ship, 28 meters below sea level.
Resellers and collectors in the sights
Discovered in 2017, the wreck is for archaeologists a source of forgotten details on regional maritime trade.
But during a dive a few months later, Hansson notices that the underwater place has been visited: a pot has disappeared.
I swore under my mask at a depth of 30 meters
", remembers the forty-something.
The wreckage of the 500-year-old marching ship was discovered in 2007. HANDOUT / AFP
Up to 20,000 boats are currently resting in the bottom of the Baltic which, thanks to its brackish water - a mixture of salt and fresh water - allows good conservation where other seas degrade wood much faster.
Wrecks like this one, located near Dalarö, south of the Swedish capital, are protected by law against theft.
But some - “
collectors and other dealers
”, archaeologists argue - see fit to dig into the depths to steal these secular objects ... and ruin historical work.
If everything is still there in the wreckage, we can tell a story as close to reality as possible, because there are no books, sketches, plans on these objects,
” says Jim Hansson.
In November 2019, the archaeologist and his team, looking for wrecks to exhibit in a future museum in the Swedish capital, discovered a new warship off Stockholm.
The wreck is believed to be the "
" of the legendary "
" which sank in the 17th century on its maiden voyage before being refloated in 1961 to be housed in a spectacular museum in the center of the capital.
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Since then, this building has been preserved from looting.
But archaeologists have noticed recent signs of intrusion near other wrecks crossed in the waters of the archipelago, where a diving permit is required.
Objects such as porcelain pieces and terracotta crockery have disappeared from at least four 17th-century boats.
Diving masks and other knives were also discovered on site.
At the start of 2020, it was therefore decided to intensify inspections to better detect visits.
We can come back and check (...) whether people have come here to loot or whether natural causes have made the wreckage disintegrate
", explains Patrik Höglund, one of the archaeologists.
Archaeologists Jim Hansson and Patrik Höglund ready to join the 16th century wreck.
JONATHAN NACKSTRAND / AFP
This time, relief: armed with a 3D map of the site around the former merchant ship, Jim and his team find that the elements of the wreck visited have not moved - the barrels of iron ore and the ship's beams are still in place.
With some 1,500 kilometers of Swedish coastline bordered by the Baltic to watch, the authorities have answered the call of archaeologists who are now sharing photos, videos and 3D maps of the wrecks.
Since the spring, the coast guard has been using their daily surveillance flights over the archipelago to monitor sites and detect any sign of unauthorized dives.
On the surface, the corvette commander, Patrik Dahlberg, admits that this job is quite different from his usual duties.
we understand the value of this work, it's useful,
” he admits.
Patrik Dahlberg, Swedish coast guard, who works to monitor the sites and detect any signs of unauthorized dives.
JONATHAN NACKSTRAND / AFP
According to Jim Hansson, the value of some items is such that it is difficult to deter thieves.
But the researcher hopes the efforts will bear fruit: "
if there is money, then people will try to take it, so our mission now is to try to have a better system