Based on chance finds by fishermen, researchers have suspected for some time that there was a sunken area of land once occupied by people in a southern region of the North Sea.

Despite challenges in exploring the area, researchers used acoustic techniques to map it out and look for further proof of civilization.

As well as finding an area of land that looks like it was previously woodland, the researchers also found fragments of flint, one of which was probably used as a hammerstone.

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With countless ferries, freighters, and tankers sailing across it every day, the North Sea is home to one of the busiest shipping routes in the world.

However around 12,000 years ago, as the last major ice age came to an end, a part of this expanse of water was still land.

A press release from the University of Wales describes how researchers suspected that this area was once was home to many people. In recent years fishermen have stumbled across cultural artifacts and remains in the North Sea that supports the theory of a sunken settlement.

British researchers have spent the last two years reconstructing the sunken landscape using data provided from various sources, including oil and gas companies and wind farm developers. Now for the first time, this lost region between Scandinavia and Great Britain known as "Doggerland" has been "reconstructed" and further evidence found to confirm settlers.

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In order to check whether people lived in this area in the past, Martin Bates, a geoarchaeologist at the University of Wales Trinity Saint David, and a team of researchers investigated three potentially interesting geological and archaeological sites in the southern North Sea.

"This is a very exciting project to be involved in," said Dr. Bates. "Here at Lampeter, our job is to examine all the cores that have been drilled into the seabed and reconstruct the geology of the changing environment over the last 100,000 years. From this information, we can pinpoint likely places on, or beneath, the seabed which might have evidence for activity by our ancestors living in this now lost landscape."

The researchers' equipment, including a parametric echosounder, sparker, grab, and videoframe. Simon Fitch, Europe’s Lost Frontiers

One challenging aspect with regards to landscaping the area is the fact that the North Sea is an incredibly busy seaway, and doesn't exactly have the most accommodating weather. Visibility underwater is also limited quite a lot of the time, given that there are various utilities crossing the water.

Naturally, these traffic, weather, and obstruction issues make it quite hard to map out the seabed.

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Taking into consideration the challenging conditions, the team used acoustic techniques and physical sampling to survey three potential spots on the seabed where settlement areas were most likely to be.

Standard geophysical techniques and a new technique called parametric sonar were then used to obtain the highest resolution images possible of deposits below the seabed.

A prehistoric forest and a river at the bottom of the sea

In Area C, the scientists were able to confirm a well-preserved land surface containing numerous large samples of peat and ancient wood, strongly indicating a prehistoric woodland once stood in that area.

In area B, Bates and his team managed to identify a large river.

On studying the area where it would have flowed back into the sea, scientists didn't just find peat remains; they also came across "nodules" of flint which may have come from submarine chalk outcrops near the ancient river and coast.

The route the researchers took shows areas of detailed survey. Map data © 2019 Google and VLIZ / Europe's Lost Frontiers

"The material recovered suggests that the expedition has revealed a well-preserved, prehistoric landscape which, based on a preliminary inspection of the material, must have contained a prehistoric woodland," said the researchers. "The recovery of stone artifacts not only demonstrate that these landscapes were inhabited but also that archaeologists can, for the first time, prospect for evidence of human occupation in the deeper waters of the North Sea with some certainty of success."

Further investigation of the archaeological artifacts has not yet taken place but initial investigations of the finds suggest that they were tools.

Among the artifacts is a small fragment of flint that may have been a by-product of stone tool manufacture.

The researchers also found a larger chunk of flint that appears to have been broken off from the edge of a stone hammer.

Stone artifacts from the area of the Southern River estuary, including a larger fragment of flint, probably used as a hammerstone. Photographs and 3D scan data by Tom Sparrow, Visualising Heritage/University of Bradford

According to the experts, the artifact was likely part of a personal toolset used to make a variety of other flint tools.

These new discoveries may help us delve a little further into the mystery of the "British Atlantis".

"Work will now proceed to refine our knowledge of the larger context of these finds and to plan further expeditions to explore these hidden prehistoric landscapes," the researchers said.