Press Release

Poole Harbour is Britain's Oldest Cross-channel Port

The story of Britain's rich and varied maritime heritage has taken a new twist following sensational new research by experts from Bournemouth University and the Poole Bay Archaeological Research Group.

Supported by the Poole Harbour Heritage Project, researchers from the University's Archaeology Group and the Poole Bay Archaeological Research Group have uncovered evidence to prove that Poole Harbour - Europe's largest natural sea inlet - is Britain's oldest working cross-channel port.

In a report published in the Autumn issue of Current Archaeology, Prof Tim Darvill, Mike Markey, and Eileen Wilkes reveal that ancient piles (wooden support posts) from within a series of jetties between Cleavel Point and Green Island have been radiocarbon dated to about 250 BC. This easily pre-dates any other significant port facility found on British shores. Artefacts from an Iron Age settlement at Cleavel Point shows that traders plying the western seaways sailed into Poole Harbour at the time to purchase/collect pottery, shale jewellery and perhaps other things too made locally in Dorset.

"The scale of the facilities now revealed around Cleavel suggests that here is Britain's first really substantial cross-channel port - the predecessor of today's busy cross-channel ferry terminal," says Prof Tim Darvill, head of Bournemouth University's Archaeology and Historic Environment Group and Chairman of the Poole Harbour Heritage Project.

Two jetties have so far been found, one projecting south-westward from Green Island the other north-eastward from Cleavel Point. Once seen as part of a causeway, these massive stone and rubble structures are separated by a deep-water channel some 70m wide. The Green Island jetty is 55m long and 8m wide. The Cleavel jetty, which has now been dated, is similar in construction and 160m long and 8m wide. The foundations of the jetties comprise wooden piles formed of cut tree trunks 12-25 cm in diameter and up to 1.6m long. The ends of the posts had been sharpened and then driven into the harbour floor. These piles were irregularly spaced, singly, in pairs, and sometime in threes. More than a dozen were recovered from recent excavations, and identifications by Nigel Nayling of St David's College, Lampeter, show that most were oak, but that three were yew and two birch.

Layers of clay, coarse sand, and flint rubble intermixed with lenses of brushwood were built up between and around the piles. The surface, which currently lies about 1m below the water and is covered in about 1m of silt, was made of stone slabs typically 5-10cm thick and 20-40cm across. Some rested directly on the squared-off tops of the wooden piles. The majority of the stone is Purbeck Limestone, but iron-cemented sandstone and chalk is also present. Flint and stone gravel was used as grouting.

"It has long been recognised that later prehistoric communities living on Britain's southern coast were heavily involved in cross-channel and along-shore trade of various kinds," Prof Darvill continues. "Excavations at Mount Batten, Devon, and Hengistbury Head, Dorset, show these and other sites like them were important ports, perhaps serving the tribal grouping in whose territory they lay. Rather less attention has been paid to Poole Harbour, despite the numerous finds and extensive occupation areas recorded since the 1950s. Much came to light when the south Dorset oilfields were scaled-up by British Petroleum in the later 1980s. Recent work provides a more robust context for these finds, and shows the existence of major prehistoric harbour constructions on a scale hitherto unknown along the English Channel coast."

Poole Harbour, located in the centre of England's south coast, is just 110km or 65 nautical miles from the Normandy coast in France. Today, Poole boasts of being one of the largest natural harbours in the world. But in later prehistoric times, the sea level was 2-3m lower than today, with commensurate changes to the position of the shoreline.

"Present evidence suggests that at Cleavel, jetties were built out from the shore to a deep-water channel, thus allowing boats to sail through into sheltered water and then tie up alongside at a well-built quay," Prof Darvill concludes. "The presence of a substantial quay at Cleavel allows the possibility that the remains of sea-going vessels lie buried in the silts; this is one of the targets for future work."

Thanks go to Mike Markey of the Poole Bay Archaeological Research Group for providing this press release.