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The remains and ruins of Grey Friars friary on the hill at Dunwich beach Suffolk east Anglia England.

Britain's Atlantis: Dunwich, the sunken city of Suffolk

The remains and ruins of Grey Friars friary on the hill at Dunwich beach Suffolk east Anglia England.

‘The Splendid City’

Mention Suffolk to most people and what probably springs to mind are pretty coastal villages and picturesque countryside but did you know that in the Middle Ages a great city straddled the middle of its coast? This place was Dunwich, now a small village home to 200 people but at its peak in 1250 it was a town of five thousand and the size of the City of London.

This is the story of a city that fell into the sea, the legend of a sunken metropolis with a fabled golden age, a powerful trading outpost that made warships for kings and sent merchant vessels to the ports of Europe. How much of this is true, and how much is the stuff of romantic tradition?

Angles to all saints: A brief history of Dunwich

There were prehistoric people in Dunwich, and the Romans likely had a sea fort there.

Later, the chief town and the original see of the Anglo-Saxon bishops of the Kingdom of East Anglia was a place called Dommoc. King Sigeberht of the Angles brought Felix of Burgundy to Britain and elevated him to bishop here in 630.

For hundreds of years, it was believed that Dunwich was this ancient capital:

‘That now forgotten and obsolete port where Bishop Felix once fixed the Episcopal stool of the East Anglian realm, whose very site is now long since swallowed up by the encroaching sea.’

The Times, 1885

In 1934, the Church revived the old title Bishop of Dunwich for use in Suffolk, but scholars now doubt whether Dommoc was, in fact, Dunwich; some located it in Felixstowe. Dunwich was, in any case, an important Anglo-Saxon settlement.

In the 9th century, the Danes came. This period of Dark Ages Dunwich is very dark indeed and was only illuminated again with the Normans.

The Norman arrival ushered in Dunwich’s time as a great centre of maritime enterprise. In 1089, the town had three churches and was the second-largest town in Suffolk, and one of the 18th largest settlements in England by population.

It was an important centre of religious patronage, and during the medieval period there were buildings for the Franciscan and Dominican orders as well as for the Knights Templar. In 1154, Dunwich had 19 churches, two monasteries, and two hospitals.

From 1215, it had a mayor, and in 1242 it was recorded as being the largest port in Suffolk. It was during the ‘second quarter’ of the 13th century that Dunwich enjoyed its heyday, according to Rowland Parker, author of the stirring history, Men of Dunwich.

Like the tales of the lost Atlantis and the mythical land of Lyonesse, the story of Dunwich seizes upon the imagination.’

W.A. Dutt, Highways and Byways in East Anglia, 1901

During this period, Dunwich merchants got ‘richer and richer’ according to Parker, and maritime commerce was constantly increasing. The harbour area would have been a hive of activity, with merchants, sailors, and shipwrights scurrying about the wharves, fish-curing sheds, shipyards and jetties. It was an important shipbuilding centre during this time and royal galleys were built and harboured there. Successive kings frequently called on the ‘men of Dunwich’ to provide ships for war and transport, and Dunwich would often flex its muscles in trading disputes and in dealings with the monarch.

Dunwich enjoyed extensive trade with Germany, the Netherlands, France, and even Spain and Iceland, not to mention relations with other English ports such as London.

It profited in goods including wine, stone, wool, and salt, but fishing was everything to the town, and Dunwich capitalised on this prized commodity. Many payments were made in whole or in part in herring, such as those to priories and to monarchs, and an 1199 charter to Dunwich from King John was paid for in part with five thousand eels.

In 1282, Dunwich was the sixth-richest town in East Anglia, but the tide was beginning to turn for the town. Disastrous storms in the 1280s and then in the 1320s resulted in severe damage through the blocking of its harbour and the destruction of hundreds of houses and community buildings. The Black Death in England (1348-49) added to the town’s woes and Dunwich continued to decline over subsequent decades, with erosion chipping away at what remained of the settlement, skilled labour leaving, and general economic decline all having a snowball effect which ensured it would never return to its past glory.

Despite a slight resurgence in its fortunes in the 15th century, Dunwich was a quarter of its peak size by 1602 and in 1832 it was declared a ‘rotten borough’.

All Saints Church finally tumbled into the sea in 1919, and bones from its graveyard still sometimes fall out of the cliff today. Eerily, too, a local legend has it that the sound of church bells can be heard emanating from beneath the waves.

Britain's Atlantis

Old Dunwich certainly existed, but was it anything like the place of our imagination? Despite the numerous medieval records of its wealth and population, many were still cautious in inferring just how big it was. Even if conceding its full extent, the notion that it was just sitting under the waves was for many a fanciful idea.

For many years, however, it was believed that the legend of ‘Britain’s Atlantis’ was just that, a romantic tale of a city beneath the waves which belied the fact that the buildings and streets of the old town had in fact just been carried out to sea and dissipated.

Locals and other interested parties had however long suspected that the sea near Dunwich contained more than just fish and sediment. In the 1970s, Stuart Bacon developed ways in which to identify building remains in what were essentially near-zero-visibility diving conditions in the North Sea.

He found All Saints church, near to the shoreline. The fact that these remnants had not vanished into the North Sea suggested that perhaps the far older ruins might still be out there – the ‘lost city’. Bacon continued to retrieve more bits of church, tomb, and other artefacts, but was still being told by experts at the time that nothing was out there.

It was not until 2008 that sonar technology provided proof of the legend, showing that the medieval ruins in fact remain largely in place on the seabed. Buildings from its heyday eight centuries ago lie in the murky depths less than a mile from the current shoreline.

Peter Murphy from English Heritage said of this survey that, ‘Everyone was surprised […] by how much of the eroded town still survives under the sea and is identifiable.’

However, much of the early medieval town is buried beneath the sandbank on the sea floor.

The discoveries of the last two decades have shown that Dunwich was a significant settlement – it did occupy an area roughly the size of the City of London. The surveys have discovered and mapped the ruins of a number of churches and other buildings, including Blackfriars Friary, St. Peter’s, and the Chapel of St Katherine. They have also found what may have been the town hall and structures associated with a port.

The 2012 Dunwich town reconstruction was made by the various archaeological and scientific organisations studying the site. It drew on contemporary sources, modern survey data, archaeological finds, coastal change analysis, and the Ralph Agas map of 1589, to give us a fascinating picture of ‘Britain’s Atlantis’. It shows among other things a large ‘market place’ a couple hundred metres or so east from the coast of the current village centre, and a dense thicket of streets and churches.

Today it is the world's largest medieval underwater town site, extending to the estimated coastline of the year 1050, which is about 1500 metres from the present shore.

Dunwich is not alone - over 150 settlements are known to have been lost to the North Sea over the last one thousand years, such as Rungholt in Germany – but recent archaeological finds have resonated with the tradition of the ‘splendid city’. David Sear described Dunwich in 2011 as having been a ‘large medieval port town’ that has been 90% lost to the sea. In conclusion, Dunwich was not only quite a sizeable place of many large stone buildings but also medieval big-hitter, a formidable, ballsy city with a lot of independence that vied with the likes of Hamburg and London.