Belgium’s long-lost coastal islands rediscovered

Scientists have successfully mapped a long-lost system of barrier islands off the Belgian coast, once resembling the Dutch Wadden Islands. The discovery was announced on Wednesday by the Flanders Marine Institute (VLIZ).

According to Soetkin Vervust, coordinator of the Testerep Project (named after the ancient sand island once located between Ostend and Westende), the central part of the Belgian coast was dotted with sandy islands for thousands of years. Around 6,000 years ago, the coastline featured large sand formations, the biggest measuring roughly 7.5 by 3.3 kilometres.

Researchers from VLIZ, the Vrije Universiteit Brussel, KU Leuven and Howest spent the past four years reconstructing the vanished landscape. It likely resembled today’s Wadden Sea: a dynamic patchwork of barrier islands, sand flats and tidal channels that served as natural coastal defences.

The findings not only shed light on the ancient evolution of Belgium’s coastline but could also help address future challenges such as rising sea levels and coastal protection. Sediment samples and well-preserved peat layers suggest the island system endured for at least four millennia.

Between the 3rd and 8th centuries, the Testerep island began to erode, though scientists are still unsure why. Around AD 700, the Stroombank sandbank off Ostend began to form where the island once stood. “By visualising what lies beneath the seabed and dating the sand and peat layers, we can fill in missing chapters of our coastal history,” Vervust explained.

^{#FlandersNewsService | © BELGA PHOTO BENOIT DOPPAGNE}