Maritime archaeologists working off the Danish coast have uncovered the remains of a colossal medieval cargo vessel that is already reshaping what experts thought they knew about northern European trade. The wreck, identified as the cog Svælget 2, is now regarded as the largest ship of its type ever found, a kind of “super freighter” from the early fifteenth century. Its scale, preservation and location near Copenhagen together offer an unusually vivid snapshot of how goods, people and power moved across the Baltic and North Seas at the end of the Middle Ages.
As researchers slowly document the timbers on the seabed, they are finding not just a big ship, but a sophisticated piece of maritime engineering that pushed the cog design to its limits. From its estimated cargo capacity to traces of rigging and hull construction, Svælget 2 is emerging as a benchmark find that will anchor future debates about medieval shipbuilding and commerce.
The discovery in a Danish ship graveyard
The wreck surfaced from obscurity during routine underwater work in a busy shipping lane between the island of Amager and Saltholm, southeast of Copenhagen. Maritime specialists from the Viking Ship Museum were called in after sonar and visual surveys suggested a substantial wooden structure on the seabed, and subsequent dives confirmed that the site was part of a broader ship graveyard where older hulls had come to rest. As the team mapped the area, they realized that one vessel, later named Svælget 2, dwarfed the others and preserved a remarkably intact cross section of a medieval freighter.
Archaeologists describe Svælget 2 as an unusual medieval freighter discovered in a deep channel known locally as Svælget, a place where currents and sediment have combined to protect wrecks for centuries. Reporting from the site notes that Archaeologists have been diving in this ship graveyard off Denmark, where Svælget 2, a 600, has stood out for both its size and state of preservation. The location, close to modern Copenhagen’s shipping approaches, underlines how the same waters have served as a maritime crossroads from the medieval period to the present.
A “medieval super ship” and the world’s largest cog
Once the basic outline of the hull was clear, specialists quickly realized they were not dealing with an ordinary cog. The vessel’s length, beam and surviving planking pointed to a cargo ship built on a scale that surpassed known examples from the Hanseatic trading world. Researchers at the Viking Ship Museum have described Svælget 2 as a medieval super ship and concluded that it is the world’s largest cog identified so far, a judgment based on comparative measurements with other excavated wrecks and historical depictions of similar vessels.
Detailed documentation from the excavation emphasizes that Archaeologists working with the Viking Ship Museum regard Svælget 2 as the World’s largest cog, a label that reflects both its physical dimensions and its exceptional preservation. Additional analysis of the hull and surviving fittings shows that Svælget 2 is not only large, but also retains traces of the ship’s rigging and other structural details that rarely survive on wrecks of this age, as highlighted in further documentation of Svælget 2. Together, these features justify the “medieval super ship” label and give researchers an unusually complete template for understanding how such a vessel was built and sailed.
Dating the wreck and reconstructing the ship
To move beyond first impressions, the team turned to scientific dating and careful timber analysis to pin down when and how Svælget 2 was constructed. By sampling the oak planks and frames and comparing their growth rings to established reference curves, specialists used dendrochronological analysis to place the felling of the trees around the early fifteenth century. That timeframe aligns with the peak of cog use in northern Europe, when merchants and city alliances relied on these broad-beamed ships to move bulk cargo between ports from the Low Countries to the Baltic.
Reports on the project explain that Dendrochronological analysis of the timbers dates the ship to around 1410, confirming that Svælget 2 belongs to the late medieval phase of cog development. Additional coverage of the find notes that maritime archaeologists in Dec reported the World’s Largest Cog Found off Copenhagen, reinforcing the identification of the wreck as a cog and situating it within a broader pattern of discoveries in the waters near Copenhagen. A separate historical overview of the site describes how a World’s largest medieval cog was found off Copenhagen and connects the wreck to a long tradition of maritime activity around the Danish capital, as outlined in a Dec entry on World shipping in Copenhagen.
What Svælget 2 reveals about medieval trade
Beyond its size and age, Svælget 2 matters because it offers a rare, three-dimensional look at how late medieval merchants organized long-distance trade. The cog’s broad hull and deep hold were designed for bulk cargo, and its structural reinforcements suggest it was built to carry heavy loads across open water rather than hugging the coast. Archaeologists estimate that a vessel of this scale could have transported hundreds of tons of goods in a single voyage, from grain and timber to wool, beer and building materials, linking producers in the Baltic with consumers and markets further west.
Specialists quoted in recent coverage argue that the wreck gives them a real opportunity to say something entirely new about how cogs were equipped for sailing, because Svælget 2 preserves details of the hull and fittings that are usually lost. One report notes that Svaelget 2’s cargo capacity was 300 tons, a figure that underscores just how much economic weight a single voyage could carry. Another account of the ship graveyard emphasizes that this medieval ship found during modern work sheds light on medieval trade across northern Europe, a point that is reinforced in the description of how medieval trade routes converged in Denmark. In that context, Svælget 2 becomes a floating piece of economic history, a physical reminder of the scale and sophistication of commerce that tied together cities from Copenhagen to the wider Baltic world.
Copenhagen’s waters as a medieval crossroads
The location of Svælget 2 off Copenhagen is not incidental. In the late Middle Ages, the narrow straits around Denmark were a strategic choke point for ships moving between the Baltic and the North Sea, and control of these waters translated directly into political and economic leverage. The discovery of such a large cog in this corridor reinforces the idea that Copenhagen and its approaches functioned as a major hub where international shipping lanes intersected, long before the modern port and bridges reshaped the coastline.
Accounts of the excavation stress that maritime archaeologists from Denmark’s Viking Ship Museum were working off Amager, near Copenhagen, when they realized they had uncovered something exceptional in the channel between Amager and Saltholm. One detailed narrative describes how a Well-preserved Medieval Super Ship Discovered Off Copenhagen Coast was recognized as a unique find by the Maritime team. Another synthesis of the evidence notes that maritime archaeologists from the Viking Ship Museum in Dec reported a Medieval ship discovered off Copenhagen that was a cog built for bulk trade, highlighting how Medieval Copenhagen sat at the heart of regional shipping networks. Additional coverage of the remains of a Medieval Super Ship that Turn Up in the Waters of the Danish capital underscores that the Remains of this vessel, found in the Waters of the strait, are part of a broader pattern of discoveries that continue to recast Copenhagen as a medieval maritime crossroads, as described in reports on the Remains of Svælget 2.
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