A Viking Age Shipyard at Kugghamn, Birka
The report details the findings of an archaeological investigation focused on maritime remnants in close proximity to the Viking Age town of Birka on Björkö, Uppland, Sweden. The study, conducted in August 2020 and August 2021, encompassed surveys utilizing GNSS receivers and drones, geochemical mapping, and the excavation of four trenches. The Archaeological Research Laboratory (AFL) at the Department of Archaeology and Classical Studies, Stockholm University, carried out these investigations.
The results reveal the existence of an extensive maritime cultural landscape in the northern part of Björkö, abundant in various types of remains. One particular feature, subjected to detailed excavation through the digging of four trenches, comprises a dug-out hollow lined with stones on the sides and bottom. Within the hollow, evidence of a wooden structure was uncovered in the form of small post-holes, accompanied by a stone frame at the mouth of the hollow facing the waterfront. This configuration is interpreted as the remnants of a boat slipway.
Discoveries such as rivets (both used and unused), carpentry tools, and slate whetstones dominate the findings, reflecting the activities conducted at the site. The overall interpretation suggests that the site served as a boat repair facility with an associated boat slipway. Notably, artifacts like glass beads, contemporaneous with the town of Birka, contribute to a general dating of the remains, possibly emphasizing its later phases.
The report concludes that this maritime construction represents a unique discovery with limited comparable examples but aligns well with other maritime remnants in the surrounding area. To fully comprehend its function and establish an accurate timeline, it is imperative to continue investigations in this significant region of Björkö.
See also: Finds from Birka
The black filled circles in Sondage 1 show the distribution of iron rivets and rivet washers measured with GNSS receivers. Note the rivets in a row (Nitar pâ rad) in the longitudinal direction. The “rivet cache” (Nitgömma) is an accumulation of used rivets near the stone at the northern edge of Sondage 1.
image: Stockholm University
Results of the mapping of near-shore remains between The Black Earth (Svarta Jorden) and Korshamn.
The facilities registered as possible jetty or boat launch remains have a light red fill and are marked marked 1 – 9. Of these, 1 – 3 lies within Birka’s city wall, the others lie outside. The light green polygons mark graves belonging to the grave field Hemlanden, here selected only to show the boundaries of the cemetery. Grey polygons mark areas with stones and boulders in the soil that have been interpreted as beach stones.
Image: Stockholm University
Digital 3D model of the stone packing in shaft 2. View to the south.
Photogrammetry, modelling and image by Fredrik Lundström
image: Stockholm University
1 Isaksson, S. et al, “En vikingatida varvsplats vid Kugghamn, Birka: Arkeologiska undersökningar av L2022:2719, Birka, Björkö,Adelsö socken, Uppland, augusti 2020 och 2021”, Stockholm: Arkeologiska forskningslaboratoriet , 2022. , p. 1 – 47