It’s been almost three weeks excavating under water here in Viking age Birka. We have made some great finds but before this wooden spoon I haven’t really found anything spectacular.
While doing the last dive for the day last Thursday I have to admit I was tired, little cold and quite anxious to get to go to dinner. I was cleaning the trench for the Friday mornings photo shooting and at first I thought I had found another bone which we find a lot from here. But on closer look it was a shape I hade never seen in a bone. Carefully I turned the first peace around and realized it was a wooden spoon!
It was broken in two pieces but they fit together perfectly. The spoon is approximately 15 cm long and 5 cm at its widest.
After this day when someone asks me what is my most exiting find I have ever made, I would have to say it’s a wooden Viking age spoon from Birka!
After two and half weeks of excavation, this year’s campaign comes closer to its end. Only a couple of days are left for the international team, to proceed which the research. But one of the main goals, to find more timbers that can most likely be related to a former harbour construction has in some cases already been achieved (check out blogpost 23/8 to get hold of some more detailed information of some of these years’ timber findings and the ones from earlier years). This gives us now the opportunity to think about how Birka’s harbour might have looked like, by taking constructions, known from excavations that have been taken place at several places in northern Europe, into account. At the same time these comparisons enable us to set the results into the broader context of the development of harbours during the Viking age as well as those from early and high medieval times.
Among the excavated timbers, especially one log sticks out. At this log, one of its ends has been worked to a peg.
In this case the peg forms a fishtail so the log can be called a “laxstjärtstimmer”. Logs with different types of pegs have been found at several sites, but their interpretation differs. One of the most common interpretations is that they served as poles in a yoke construction. A yoke needs at least of two poles, which form, together with a third timber, a stable construction. One way to connect the poles was to carve their upper ends to a peg and putting the third timber with holes at the ends above them. Such constructions have been used for bridges in inland waters, as well as for harbour related facilities like docks and jetties. These kinds of bridges are known from Viking age Scandinavia, but also from the southern Baltic, where Slavonic tribes settled.
Another interpretation that might fit the fishtail peg, is, that this end has been used to drive the other end of the log into the sea ground. To manage that a rope has been attached to the peg and with the help of a large three pole, the log could be lifted upwards in order to ram it deeper into the ground. When the log was into position, the peg has been cut off. If this interpretation, which was made up for the bridge of Ravning enge in Denmark, would fit, it would mean that this log has never been part of any construction, because the peg is still at its place.
A third interpretation that could be likely is that the log has served as a pole, to tie ships to it. Such poles are called “Dykdalb”, and could stand by itself or be part of a more stable construction. This interpretation would also explain the fishtail peg that prevents ropes from slipping of. A rope found close to the log may support this interpretation.
For instance “Dykdalb”, without pegs, but with ropes still attached to it are known from the Viking age settlement of Hedeby and the late 11th/early 12th century harbour area of Schleswig.
To sum up the mentioned examples, it seems likely that the “laxstjärtstimret” found in the Birka harbour was part of a harbour facility. Probably a yoke based construction, like a dock or standing alone and serving as a “Dykdalb”.
Several other logs that showed up during the excavations, doesn’t have such clear construction features. Mainly because their ends have been rotten, burned or the logs have been part of a different type of construction. Together with the stone assemblies the logs might have belonged to a jetty. One may think of a wooden, probably log cabin like construction filled with stones. Such kinds of jetties are well known from different places from Viking age and medieval Norway. They enabled ships to moor alongside in order to be easier loaded or unloaded.
So now we can see that the current excavation has been (and is still) able to gain more information about the facilities in the Viking age harbour of Birka, while several parallels from different places in northern Europe enlighten the dense networks that existed during the Viking age.
Blogg by Felix Rösch
Photos: Maija Huttunen/Pintafilmi Oy
Det här är fjärde säsongen som vi gräver i sjöbottnen utanför Birka. Vi kan idag bekräfta att den yttre hamnen har haft timmerkonstruktioner på hamnbassängens botten. Men hur hamnanläggningen i helhet har sett ut kan vi inte säga. Inte ännu i alla fall.
Med årets schakt som mäter 6 m2 har vi under de senaste årens grävningar grävt totalt ca 25 m2 på olika platser i botten rakt utanför det gamla stadsområdet. 25 m2 utgör ca 0,2 % av det bottenområde som vi uppskattar innehålla lämningar från hamnen utanför Svarta jorden. Ungefär hälften av den grävda ytan har grävts under 2011 och 2012 i två sammanhängande schakt. I dessa schakt som grävts ner till cirka en meters djup har vi förutom fina välbevarade fynd inbäddade i det vikingatida kulturlagret påträffat rester av timmerkonstruktioner. Och vad menas då med det? Jo, nere i schakten så har vi påträffat furustockar som ligger parallellt på botten. De ändar av timren som är bevarade är bearbetade på olika sätt. Två av timren är tydligt spetsade i ena änden vilket man förmodligen gjort för att kunna slå ner pålarna i botten. En del timmerändar är försedda med tappar och ett timmer som påträffades igår har en tillyxad knopp som påminner lite om en laxstjärt om man ser den från sidan.
I anslutning till ”laxstjärtstimret” påträffade vi idag även två tjocka rep, tillverkade av lindbast, som kan höra ihop med timret. Tidigare år har vi påträffat en hel del rep på botten, ofta i anslutning till kraftiga timmerstockar.
Photos: Maija Huttunen/Pintafilmi Oy
Stockar sammanfogade med rep verkar ha varit en vanlig företeelse i den yttre delen av Birkas hamn. En av stockarna i det område som vi nu gräver har med hjälp av C14-metoden tidigare daterat till 800-talet e. Kr. Eftersom det timret låg i samma nivå som de flesta andra timren i schaktet, samt att timren har samma dimensioner, är det troligt att resten av timren i schaktet är från samma tidsperiod. Timrens ursprungliga längd är okänt eftersom furustockarna i stort sett endast är bevarade nere i botten. De delar av timren som en gång stuckit upp ovan botten är sedan länge borteroderade. Annat är det med ektimren som fortfarande på sina platser reser sig flera meter över botten.
Timren som vi nu har att göra med i årets och förra årets schakt kommer med största sannolikhet från en raserad timmerkonstruktion från 800-talet som sammanfogats med rep, i alla fall delvis. För att komplicera det hela ytterligare så måste vi ta i beaktande att vi kan ha att göra med flera faser av olika hamnanläggningar från en tidsperiod på 300 år! Lägg dessutom till att dylika anläggningar håller i max 10 år innan de behöver omfattande renovering. Årets undersökning blir dock ytterligare en pusselbit för förståelsen av Birkas hamn, i ett pussel med minst tusen bitar!
Photo: Maija Huttunen/Pintafilmi Oy
Since our water pump engine broke down in the morning and our team was waiting for a new one, we got some spare time to do some check diving. Jens had mentioned earlier that the underwater areas surrounding the Björkö island have been under a recent multibeam survey. The company that did the survey had made a list of anomalities, with their coordinates. One spot was a possible wreck near Adelsö island - so by boat it was only a few minutes away from our field camp. None of these possible sites are currently to be found in the Swedish Underwater Cultural Heritage register (Fornsök), so we were quite eager to find something new.
Our plan was to side scan the area based on the coordinates we had been given. Before we left Jens made gps-marks to our boats sea chart so that we had an idea were this wreck was supposed to be. After a few minutes of side scanning we got a nice picture of something that clearly seemed like a shape of a wreck. After a few more rounds around the spot we got confirmation. The bow, stern and mid ship with some frames was clearly visible in the sonar picture. We lowered a buoy to some 10 meters away from the wreck site and were ready to jump in to the water.
After we reached the bottom at around 4 meters we took a bearing towards the wreck site. Visibility was roughly 1-2 meters but there was a lot of natural light. We ran into planks and constructions that seemed to be part of the starboard side of a vessel. Right after the planks we saw the remaining of the hull.
We knew that the bow was pointing north so we started to explore the area counter clockwise towards the bow. The ship was approximately 20 meters in length, around 5 meters wide and she was clearly lying straight on her keel. While we moved towards the bow it seemed that side planking started to be in better condition than in the mid ship area and actually you could see a clear side of the hull – inner planks, outer planking and the frame. The bow was intact and rose up from the bottom some 2.5 meters really nicely.
Above the bow depth was only 1.5 meters and bottom was roughly 4 meters. The port side had clearly seen more damage. Right after the bow the side of the hull had fallen and you could see some bottom frames sticking out. Actually almost the whole port side had collapsed next to the ship.
Stern was still intact but the way it had been constructed seemed a bit different from what we had been used to - it was only vertical planks that had been connected to the hull. We didn´t find any stern post from the inside and no visible marks of any post being ever attached was to be seen. Lower part of the stern was straight V-shaped, supported with iron framing from the outside in a way I had never seen before. Rudder had fallen of and it was behind the stern.
Inside the keel there was some kind of iron bar sticking out so it might be that the vessel actually had an engine and a propeller.
After taking some looks at the stern we turned back to follow the keel line back to the bow. The keel was visible in the mid ship area. Some lower level deck planks were still visible near the bow area. Also some stones, probably ballast or stones used for the scuttling of the ship were found.
It seemed that someone might have been repairing and changing the constructions a bit. The hull had been, and still was, very strongly built. It possibly had iron knees of which a few were still visible. The shape would suggest that she was probably built somewhere in the late 19th century. All in all a very nice dive and a new wreck is found. There are still a lot of other places to check so maybe we find something else as well.
Text: Ville Peltokorpi
UW Photos: Maija Huttunen
Surface Photos: Eveliina Salo