Vote 2020 graphic
Everything you need to know about and expect during
the most important election of our lifetimes

Prehistoric Humans Built a Wall to Keep Out the Sea—But It Failed

Artist’s reconstruction of the Neolithic village and the 7,000-year-old seawall.
Artist’s reconstruction of the Neolithic village and the 7,000-year-old seawall.
Image: J. McCarthy and E. Galili

A 7,000-year-old seawall has been discovered off the Israeli coast, and it’s now the oldest-known defense against rising sea levels. The seawall eventually failed, and the village had to be abandoned, in what’s serving as an ominous lesson from the past.

Advertisement

The Tel Hreiz archaeological site is located off the Carmel coast of Israel and once hosted a vibrant Neolithic community. This Mediterranean settlement thrived for hundreds of years, as its villagers hunted gazelle and deer, farmed cows and pigs, fished for tilapia, raised their dogs, and manufactured copious amounts of olive oil.

All seemed well, but this community was completely oblivious to something we’re all too familiar with today: massive amounts of melting ice. But whereas we’re responsible for the current climate catastrophe and the associated rise in sea levels, these Neolithic people were completely innocent. The Pleistocene and the last major ice age had come to an end just a few thousand years before.

Advertisement
Cross section illustrations showing the submerged village as it appears today (top) and how it appeared during the Neolithic period (bottom).
Cross section illustrations showing the submerged village as it appears today (top) and how it appeared during the Neolithic period (bottom).
Image: J. McCarthy, E. Galili, and J. Benjamin

They couldn’t have known that, of course, but even still, the original settlers wisely built their village 3 meters above sea level. With each passing generation, however, the villagers would have noticed something rather frightening: The waters of the Mediterranean were getting higher and higher.

Indeed, according to new research published this week in PLOS One, the rising sea levels would’ve been noticeable across a person’s lifespan, as they rose at an alarming rate of 4 to 7 millimeters each year, or around 70 centimeters (28 inches) every 100 years. Reluctant to leave their cherished settlement, and to protect against the increasingly powerful waves and the destructive effects of erosion, the Tel Hreiz villagers decided to take matters into their own hands by constructing a 100-meter-long (330 feet) seawall that ran parallel to the shore.

The seawall may have helped for a while, but it ultimately failed, and the village—after nearly 500 years of continuous occupancy—had to be abandoned.

Advertisement

Such are the findings of the new PLOS One study, which involved an international collaboration of scientists from the University of Haifa, Flinders University in Australia, the Israel Antiquities Authority, and the Hebrew University. The seawall, which is today submerged under 3 meters of water, was constructed some 7,000 years ago, and it’s now the oldest known coastal defense system in the archaeological record. It’s an exceptional find, as infrastructure improvements such as these didn’t start to appear in the region until the Bronze and Iron Ages.

Importantly, the new research, led by archaeologist Ehud Galili from the University of Haifa, shows that humanity’s battle against rising sea levels dates back for thousands of years.

Advertisement
Model showing the location of the Neolithic village compared to the how the beach looks today.
Model showing the location of the Neolithic village compared to the how the beach looks today.
Image: J. McCarthy, E. Galili, and J. Benjamin

The submerged Tel Hreiz site was originally discovered in the 1960s, but it hadn’t been thoroughly explored by archaeologists until recently. Since 2012, the site has yielded various architectural structures, artifacts, the remains of both humans and animals, and now, the ancient seawall.

Advertisement

The seawall, as the new research suggests, was nothing too fancy, having been built by piling large boulders atop each other. That said, it likely required a lot of work and coordination to build. The seawall’s length, the use of big boulders sourced from outside the community, and its careful arrangement on the shore “reflect the extensive effort invested by the Neolithic villagers in its conception, organisation and construction,” wrote the authors in the study.

Naturally, this prehistoric history lesson serves as a dire warning for us today.

Advertisement

Self-inflicted climate change is predicted to lift the oceans by as much as 1.7 to 3 mm each year over the course of the current century, according to IPCC estimates. That’s smaller than what was experienced during the Neolithic, but these sea level rises will still be problematic for coastal communities. This will inevitably result in the construction of more modern seawall defenses, but the ocean, as our Neolithic forebears witnessed themselves, is powerful and unforgiving. Like them, we too may have to reluctantly abandon our cherished communities.

Advertisement

George is a senior staff reporter at Gizmodo.

Share This Story

Get our newsletter

DISCUSSION

celer-aqua
celer.aqua

How large were these boulders and how would neolithic humans have moved/placed such items to built a seawall?