The training at Ulster University was for three days. One day of familiarising with the equipment and the survey area, a day of surveying, and a day of data processing. We were quite lucky with good weather, surprisingly for Ireland. Kieran had chosen the survey area for the training at Lough Beg, Northern Ireland, where a log boat is supposedly located in the vicinity of a crannog in the lake. We surveyed around the crannog following or trying to follow pre-determined survey lines in as much as the wind, current, and depth of the lake allowed. Since the purpose of the survey was to collect side scan sonar data, it was necessary to reduce the noise from the motor. We ended up surveying on a speed of 2-3 knots, realising that the data we were collecting was not the best, but it was good enough for the training exercise. The shallow parts of the lake were quite difficult to survey. We did get to see many posts showing up on the display unit and lots of vegetation which was also getting stuck to the motor’s propeller.

The survey was followed by a day of data processing using ReefMaster and SonarTRX. The former software allows to quickly review the data, locate anomalies, and generate a bathymetric map. The SonarTRX on the other hand is used to process the data by editing the lines of surveys one by one in order to get the best results from the collected data. It then permits to generate a mosaic from the survey lines which can be imported into GIS (Geographic Information Systems). Working through the software took almost a whole day, familiarising with the tools, editing, and exporting capabilities. We tend to assume that once the data is collected, the hard part is over, but in fact processing the data is much more demanding, it is a science and an art (quoting both Kieran Westley and Rorey Quinn). The nice mosaics and images we see often in marine geophysics are the result of long hours of computational work by dedicated individuals.

Finally, this training was concluded with a visit to the Giant’s Causeway, a walk along the incredible Irish coastline, a visit to a local pub, and good times with good people, all thanks to the Centre for Maritime Archaeology at the University of Ulster, particularly Dr Kieran Westley and Dr Colin Breen, and to the Honor Frost Foundation for their support.

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As learners active on our MOOC ‘Shipwrecks and Submerged Worlds’ have learned during week 1, maritime archaeology does not always necessarily take place underwater. What we study is human engagement with the seas and the oceans and often, the evidence for this engagement is now to be found on land. One area that is of specific interest to me are harbour-sites, the interface between land and water par excellence, and the stage for a lot of human activity.

Only a couple of weeks ago, the University of Southampton conducted a survey at the ancient harbour site of Winchelsea in East Sussex (United Kingdom). Winchelsea, refounded in the 1280’s after severe coastal erosion of its original site, was a major planned royal port. Until its decline from the middle of the 14^th century, the town was an important member of the Cinque Ports confederation and one of the principal international ports of the English realm.

Perhaps surprisingly, even though it was the very reason for its existence, very little is known about Winchelsea’s waterfront and the survey was the first step in rectifying this lacuna. Due to the silting of the harbour, what was once a fairly large river canal, is now a small stream. This does mean however, that a substantial part of the ancient port might be preserved underneath some of the fields just north of the Winchelea hill.

A variety of methods were deployed to survey the fields underneath which the port is thought to be located, some of which you will familiarize yourself with in week 3. The results of the survey are still being processed and interpreted, but we can already reveal a sneak preview here.

At the location where private waterfront plots are thought to have been located, anomalies were found at right angles to one another. Current thinking is that these are drainage ditches dug to clear the water to subsequently build something more structural there. This would correspond well with how these plots are described in the surviving Rental of 1292 which describes them as ‘perilous at all flowings of the tide’.

The second field is more of an enigma. Three separate anomalies were found that are of interest. In the southwest corner, two ditches seem to run at a right angle to one another. Perhaps these are foundation-ditches for some sort of structure that was built there, but this is pure speculation so far. In the very northern end of the field, possibly something structural was found. This might be a storehouse known from mid-to-late-sixteenth century historical records. However, also this must remain speculative without excavation. Finally, between these two features, a fairly large ditch was dug, either for drainage or sewage. More information on the survey will become available on my research blog over the coming weeks.

If you want to learn more about Winchelsea, David and Barbara Martin wrote an excellent book summarizing most historical and archaeological work in 2004 while David Martin and David Rudling compiled most excavations in the town up until the year 2000.

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