While probing the Baltic Sea's depths, Finnish divers uncovered an unexpected find: an extraordinarily well-preserved wreckage that dates back approximately 400 years.

The discovery of what seems to be a fully undamaged Dutch merchant ship from the 17th century by volunteer divers from the non-profit Badewanne team was a great surprise because they typically find destroyed 20th century artifacts lost during the maritime battles of World War I and WWII.

The vessel, a Dutch "fluit" (or "fluyt"), was discovered in the easternmost Baltic Sea seas close to the mouth of the Gulf of Finland.

The Badewanne diving crew found this Dutch time capsule lying on the bottom, nearly entirely intact and maintained, at a depth of about 85 meters (about 280 feet).

The ship is otherwise frozen in a kind of 17th century stasis, the team claims, thanks to the characteristics of the water in this part of the sea, where a combination of low levels of salinity, temperature, and light can enable sunk wrecks to survive virtually unchanged for hundreds of years. The ship shows only minor damage sustained from subsequent pelagic trawling with fishing nets.

In warmer seas, wood-boring animals proliferate and can cause great harm to artifacts like this, but in this case, the Baltic's chemistry and the mystery surrounding the fluit's sinking have left us with a magnificent artifact.

The divers claim that even the ship's holds are full, still holding its store of supplies and goods from the time when Dutch cargo ships predominated seaborne trade in this region of the world, in part because of the innovative developments displayed by the fluit itself.

These vessels, which initially appeared in the 16th century, made all kinds of sacrifices for their vital cargo. The three-masted fluit bore a cost-effective and spacious design that was fully meant to maximize cargo capacity, unlike other boats of the era that could alternate between duty as commerce ships and war vessels.

Because of this, it could carry up to twice as much cargo than competitors' ships, and cutting-edge rigging technologies made sure that even tiny crews could master the fluit's nimble sailing talents. This also made the fluit a more profitable ship to sail.

Despite the design's popularity and success during the 16th and 18th centuries, only a small number of fluits still exist today. Additional research on this particular find might turn out valuable information on these priceless artifacts.

"The wreck reveals many of the fluit's characteristics but also some unique features, not least the construction of the stern," claims maritime anthropologist Niklas Eriksson from the University of Stockholm in Sweden, who will collaborate with Finnish authorities and others to research the discovery.

"It's possible that this is a prototype for the design. Thus, the wreck presents a rare chance to study the evolution of a ship type that sailed all over the world and served as the instrument that created early modern globalization."