Researchers studying the Black Sea, one of the most unique bodies of water in the world, have uncovered a veritable time capsule of ancient ships hidden in its depths.

The discoveries, which include dozens of shipwrecks, are part of an international expedition to map in unprecedented detail the submerged ancient landscapes of the Black Sea. Over the last 21,000 years, since the end of the last Ice Age, water levels in the basin have shifted upwards dramatically, flooding vast swaths of the surrounding landscape.

"We're endeavouring to answer some hotly-debated questions about when the water level rose, how rapidly it did so and what effects it had on human populations living along this stretch of the Bulgarian coast of the Black Sea," Jon Adams, principle investigator on the Black Sea M.A.P. project, said in a statement.

To peer thousands of feet into the depths, the research team is utilizing state-of-the-art Remotely Operated Vehicles (ROVs) that feature some of the most advanced underwater survey systems in the world. The Black Sea was an important commercial trading route for ancient civilizations like the Greeks, Ottomans, and Romans, so the team expected to find shipwrecks. But what they captured through the high-tech sensors of the ROVs is nothing short of astonishing.

Black sea shipwreck The 3-D image of a preserved medieval shipwreck, with foremast still reaching for the surface, was created from more than 4,500 high-resolution photos. (Photo: Rodrigo Pacheco-Ruiz)

“We’ve never seen them this complete,” Adams told New Scientist. “Normally, it’s just bits of the lower hull, but here we have much upper-deck material.”

The stunning preservation of the vessels, some dating to the Byzantine Empire, is due to the unique water composition of the Black Sea. Originally a freshwater lake, it was filled with salt water after the last glacial period. Today, it exchanges water with the Mediterranean Sea and some of Europe's largest rivers, resulting in two distinct water layers. While the upper, less-saline layer (from 0 to 600 feet) supports life, the lower, heavier layer down to the seabed is completely absent of oxygen and devoid of organisms. As a result, the wrecks of the Black Sea have become well-preserved, undersea time capsules.

Black sea shipwreck Preserved rigging and carved wooden beams can be seen on this wreck dating back several centuries. (Photo: Rodrigo Pacheco-Ruiz)

As for those beautifully detailed images, each of which took days to render, Adams says it's all thanks to a new state-of-art imaging technology called 3-D photogrammetry.

“We took thousands of high-quality stills and video around the whole of each wreck,” he said. “Software calculates the positions of millions of points in 3-D space, generating accurate, detailed 3-D images of each wreck.”

Byzantine wreck black sea A wreck possibly dating back over a 1,000 years to the Byzantine Empire is just one of the dozens discovered so far by the expedition. (Photo: Rodrigo Pacheco-Ruiz)

With the expedition ongoing, it's likely that the Black Sea will give up more of its secrets in the coming months. To follow along with the expedition, check out the group's official site.

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.

High-tech imaging captures haunting medieval shipwrecks
An expedition mapping submerged ancient landscapes under the Black Sea has discovered a well-preserved 'shipwreck graveyard' dating back centuries.