Diving in Knudedyb

10 11 2007

A first one week underwater survey in Knudedyb took place in November 2007. It was carried out by Mikkel Thomsen from the Viking Ship Museum in Roskilde together with a team of MAP students and lecturers. The dive boat provided by the Viking Ship Museum was moored at Kammerslusen, a lock at the entry to the Ribe river, approximately ten nautical miles from the dive site.

After the dive in Knudedyb

After the dive in Knudedyb

Despite of bad weather, three dives on two different anomalies could be conducted in four dive days. Because of strong tidal currents, diving was limited to slackwater periods and underwater visibility was low.

Using circular searches around the positions of promising anomalies discovered during the side scan survey, the seabed was searched for signs of the medieval Knudedyb wreck. Already during the first dive the diver discovered a plank and a keelson on the sandy seabed. Both objects were recorded in more detail and photographed during a second dive.

Plank and keelson were disarticulated and no sign of a wreck site could be found during further circular searches. While the plank is probably of medieval date, the keelson is almost certainly part of a younger wreck.

The diver survey confirmed the high archaeological potential of the Knudedyb area. But as the strong currents and quickly shifting sands make the detection of wreckage a difficult process, further diving is necessary in order to find the remains of the medieval Knudedyb wreck. More pictures of the survey can be found here and a first report is published in the Maritime Archaeology Newsletter from Denmark.


Geophysical survey in Knudedyb

10 07 2007

In August 2007, the area in Knudedyb in which the medieval ship timbers had been discovered was surveyed with a side scan sonar in order to locate the associated shipwreck. The survey was carried out by students and staff of the Maritime Archaeology Programme in conjunction with the Viking Ship Museum in Roskilde. An Edgetech 4100 sonar was kindly provided by the local firm MacArtney A/S in Esbjerg.

Sidescan sonar capture on board the trawler Ho Bugt

Sidescan sonar capture on board the trawler Ho Bugt

The trawler E4 Ho Bugt was used as a survey vessel and the two fishermen who originally discovered the ship timbers guided the archaeologists to the area where they found the wreckage. During a five hour survey, 10 lines were run. Although a number of smaller anomalies were visible in the data, none of these could be immediately associated with a medieval shipwreck.

After post-processing, the most promising anomalies were chosen for a future diver inspection.