Today, land reclamation has seen places like Hong Kong and Dubai build over their seas to create inhabitable land.
It turns out ancient humans had their own version of land reclamation. Throughout the British Isles, 'crannogs' or ancient artificial islands survive to this day.
The islands were built by prehistoric people and can still be seen in rivers, lakes, and sea inlets.
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New research from the Universities of Southampton and Reading has revealed previously unknown details about these ancient manmade creations.
Much like Stonehenge, the origins of crannogs are shrouded in mystery, though the new findings suggest many of them are older than previously thought.
In fact, a dive into the waters around some of these islands yielded pottery from the Neolithic period, indicating they were built as early as 3640 BCE — making them older than the Stonehenge.
There are 570 crannogs throughout Scotland. While we will likely never know exactly why they were built, archaeologists and historians speculate that it was likely that they were initially built for defense purposes.
Until recently, it was thought that the construction of the crannogs dated back to about 800 BCE. In the 1970s, radiocarbon dating of excavations caused this number to be revised and pushed back further in time.
In 2012, however, Chris Murray, a resident of the Isle of Lewis, found well-preserved Early and Middle Neolithic pots on the loch bed. Further dives found similar yields at nearby crannog sites.
Unraveling the mystery
A team of archaeologists carried out ground and underwater surveys of the manmade islands. These surveys included using techniques such as photogrammetry, excavation of sites, and paleoenvironmental coring.
Radiocarbon dating has also conclusively proved that the crannogs date to a period between 3640 and 3360 BCE, the researchers claim.
"These crannogs represent a monumental effort made thousands of years ago to build mini-islands by piling up many tons of rocks on the loch bed," Fraser Sturt, an archaeologist at the University of Southampton told New Atlas.
"It appears most probable that many more Neolithic crannogs will be found. It is very exciting to think about the potential that these sites hold for improving our understanding of the past."