A photogrammetric (3-D ) model of the stern of the ancient shipwreck found in the Baltic Sea (Credit: Deep Sea Productions / MMT)

A perfectly-preserved wreck that has lain unnoticed in the icy waters of the Baltic Sea, between Sweden and Estonia, for over 500 years, has finally been discovered. The European vessel was first detected in 2009, when a sonar survey by the Swedish Maritime Administration indicated a large object in the area. However, it was not until early 2019 that maritime archeologists from the University of Southampton in England and Sweden-based marine survey specialists MMT found evidence of the sunken ship using underwater robotic cameras.

When the team returned to capture high-resolution images of the 60-foot long shipwreck, which lies at a depth of around 393 feet (120 meters), they were stunned to discover it was 99 percent intact. The scientists, who revealed their findings on July 22, 2019, attribute the Okänt Skepp​​​​​'s ('Unknown Ship' in Swedish) pristine condition to its location in a part of the Baltic seabed, where the oxygen levels are deficient. Since most marine life is unable to survive in this environment, it reduces, or completely eliminates, the number of microorganisms that feast on rotting wood.

The shipwreck's location in an oxygen-depleted zone may have helped preserve the boat (Credit: European Geosciences Union /CC-BY-SA)

Dr. Pacheco-Ruiz, who led the MMT effort, said: “This ship is contemporary to the times of Christopher Columbus and Leonardo da Vinci, yet it demonstrates a remarkable level of preservation after five hundred years at the bottom of the sea, thanks to the cold, brackish waters of the Baltic. It’s almost like it sank yesterday – masts in place and hull intact. Still on the main deck is an incredibly rare find – the tender boat, used to ferry crew to and from the ship, leaning against the main mast. It’s a truly astonishing sight.”

A photogrammetric (3-D) model of the shipwreck from the top (Credit: Deep Sea Productions / MMT)

The scientists are unsure what caused the Okänt Skepp​​​​​ to sink, or the fate of its crew. However, the vessel's guns, which were in their "ready to fire" positions, and its damaged long aft-castle — the raised part of the upper deck at the ship's stern — indicate it may have been the victim of a naval battle. Since the boat dates back to the early 16th century, historians speculate it may have sunk during Sweden's three-year independence war with its Danish rulers between 1521 and 1523. Alternatively, it could also have been involved in the border dispute between Russia and Sweden from 1554 to 1557.

A photogrammetric (3-D) model of the shipwreck's bow with the anchor still in place (Credit: Deep Sea Productions / MMT)

Regardless of why it sank, the Okänt Skepp is by far the best-preserved shipwreck ever found from the Age of Exploration era. Lasting from the early 15th century to the end of the 17th century, it was the period when Europeans traveled the world by sea in search of new trading routes and partners, as well as goods such as gold, silver, and spices.

Even more exciting is that the vessel closely resembles the Pinta and La Niña, which Christopher Columbus famously steered toward North America. The scientists, who continue to investigate the shipwreck, hope the boat's design will reveal some of the technologies available to the famed Italian explorer during his epic 1492 voyage of discovery.

Resources: Independent.co.uk, southampton.ac.uk, livescience.com