I have been there, and there are burial mounds in ever direction. Evidence abounds of a large concentration of ancient activity throughout the area of Birka itself and the surrounding countryside. It has long been known that the island saw a great deal of trading activity from the Vendel Period through the Viking Age.
A link at the bottom of this excerpt will take you to the paper that details this project from a scientific viewpoint. It is excellent and comprehensive, and I highly recommend it to interested parties. (Ed.)
JANUARY 22, 2017 BY MEDIEVALISTS.NET
Birka, Sweden’s oldest town, has long been a major source of our knowledge about the Viking Age. New geophysical research has now uncovered the ninth-century manor of a royal bailiff at this site.
|Reconstruction Viking age manor – reconstruction by Jacques Vincent – photo courtesy Stockholm University|
During spring of 2016 a number of large presumed house terraces were identified by the researchers at Korshamn, which lies outside the town rampart of Birka, which itself is situated on an island in Lake Mälaren, near Stockholm. As a consequence high resolution geophysical surveys using ground-penetrating radar were carried out in September 2016, which revealed a major Viking period hall on the site, with a length of around 40 meters. Based on the land upheaval the area of the Viking hall can be dated to sometime after 810 AD. The hall is connected to a large fenced area that stretches towards the harbour basin.
“This kind of Viking period high status manors has previously only been identified at a few places in southern Scandinavia, for instance at Tissø and Lejre in Denmark. It is known that the fenced area at such manors was linked to religious activities” says Johan Runer, archaeologist at the Stockholm county museum.
During the survey a predecessor for the Viking Age manor was also identified at the site: a high status manor that existed during the Vendel period, prior to the establishment of the Viking Age town of Birka. Both the identified buildings and their continued use from the Vendel period to the Viking Age correlate well with the “ancestral property” of Birka’s royal bailiff Herigar as mentioned in Rimbert’s Vita Anskarii. Herigar was Christianized by Ansgar, archbishop of Hamburg-Bremen, during his first mission c. 830 AD, and he built the first church on his land.
“The consequences of our discoveries cannot be overestimated: in terms of the emergence of the Viking town of Birka, its royal administration and the earliest Christian mission to Scandinavia”, says Sven Kalmring, researcher at the Zentrum für Baltische und Skandinavische Archäologie, Schleswig.
“The results highlight the benefits of using non-intrusive geophysical surveys for the detection of archaeological features and, once again, prove to be an invaluable tool for documenting Iron Age building remains in Scandinavia”, says Andreas Viberg, researcher at the Archaeological Research Laboratory at Stockholm University.
The results has been published in the journal Archäologisches Korrespondenzblatt – click here to read the article: At Home with Herigar: a Magnate’s Residence from the Vendel- to Viking Period at Korshamn, Birka (Uppland / S)