A long-lost medieval trading site has been located beneath mudflats off Germany’s western coastline.
Rungholt was long thought to have disappeared when it was inundated by massive storm tides in January 1362, which claimed settlements along the west coast of modern-day Germany and Denmark.
Scientists from Kiel University, Mainz University, the Center for Baltic and Scandinavian Archaeology and the State Archaeology Department Schleswig-Holstein have now confirmed its location beneath mudflats in the world heritage Wadden Sea using a range of archaeological and geophysical methods.
Detecting a two-kilometre-long sequence of artificial mounds upon which medieval settlements were built near the tiny Wadden Sea island Hallig Südfall, researchers spotted decayed structures suggestive of church foundations.
Sediment cores were then extracted from the site before excavation at low tide. The scale of the church is consistent with those constructed in the North Frisian region along Germany’s west coast, and likely meant it served as the central point of the Rungholt trading site.
It joins previous findings of medieval drainage systems, dykes, harbour gates and two smaller churches.
“The special feature of the find lies in the significance of the church as the centre of a settlement structure,” says archaeologist Dr Ruth Blankenfeldt.
“In its size, it must be interpreted as a parish with superordinate [superior] function.”
The Wadden Sea is the planet’s largest system of tidal mudflats covering an area of 11,500 square kilometres and today it is an important sanctuary for migratory birds.
Back in 1362, a massive storm surge that reshaped this region resulted in thousands of fatalities, earning the label Grote Mandrenke (the Great Man Drowning).
While sophisticated dykes and sea walls have been installed to divert water from storm surges that threaten property in recent times, hazardous weather events have increased threefold in the last 40 years, with ocean levels expected to rise further in the region because of climate change. These events also threaten the cultural heritage of the region.
“We selectively take sediment cores that not only allow us to make statements about spatial and temporal relationships of settlement structures, but also about landscape development,” says Dr Hanna Hadler, a geoarchaeologist from Mainz University.
“Around Hallig Südfall and in other mudflats, the medieval settlement remains are already heavily eroded and often only detectable as negative imprints.
“This is also very evident around the church’s location, so we urgently need to intensify research here.”