Two new excavation reports

Recently have two new excavation reports from the project been completed. The first deals with the 2013 excavations at Offerlunden (sacrificial grove) and the Östra terrassen (eastern terrace), while the second cover investigations made in 2014 around the Högåsen burial ground.

The Offerlunden excavation took place in- and outside a major depression, which in the early 20th c. contained water. The name, Offerlunden, derives from the famous Swedish 1600th c. scientist Olof Rudbäck the elder. He argued for a pagan sanctuary in Uppsala with grooves, wells and altars. Our main objectives were to check the preservation conditions for prehistoric and medieval layers in the depression and to examine the potential for well-preserved remains of insects, macrofossils and pollen. These kinds of data have so far been difficult to recover in Gamla Uppsala, due to dry conditions and few excavated wells. The second goal was to examine if a deposition animal bones found in 1972 might represent ritual depositions in the well.

The excavation showed that that the depression has been redesigned more than once, especially during the 19th/20th centuries, when it was a dirty combination of a duck pond and a rubbish pit. There were no signs of deposited of animal bones or layers with well-preserved floral or insect remains in the trenches. However, we found a hearth, 14C-dated to 7th c, which was dug into naturally deposited sand layer. The stratigraphic sequence indicates that the depression existed already by the Vendel period. By then it hardly contained water as it did in the early 20th c.

On basis of our excavation results in combination with an earlier test trench, it seems like the depression has been created before or during the 7th century. Later has a hearth been placed near the bottom of the pit. This might simply be a quarry pit that has been dug in order to get building material for the great mounds.  A small trial pit dug just the depression showed some settlement features, which together with the said hearth connects larger settlement area from the Late Iron Age, placed by foot of the great mounds.

At the eastern terrace we found traces of an older land surface and a stone filled foundation trench with postholes with corresponding activity layers. The foundation trench could be observed visually in the grass along the eastern side of the terrace. It has been 14C-dated to 1160-1290 CE. This period is very close to the period in use of the cathedral, 1164-1273 CE. However, it was not clear whether the foundation trench constituted a part of a building or a bounding construction. Beneath the foundation trench were sandy layers and a stratigraphically older, very large cairn identified. This cairn has an upper flat surface and we could follow how it sloped down to the east. It has the shape of a partially curved cairn with a prevalence of at least 15-20 m in diameter. Bones from the layers immediately above stone cairn was 14C-dated to the middle of the 7th century.

Section through the mound with light-dark layers.

The report describes the state of knowledge after the excavations in 2013. The subsequent excavations in 2015 has revealed that that the cairn and the small earth mound on top of the terrace represent the remains of a once very large great mound. The cairn is in fact the biggest found so far in Middle Sweden. The terrace is built from the earth of the mound. It has simply been levelled out in probably the 12th century, maybe because it has blocked the view for the cathedral. After that has the foundation ditch for a palisade around the cathedral area been placed on the terrace.

In 2014, focus was set at two areas adjacent to the large burial ground of Högåsen in Gamla Uppsala

The first feature was a strange, about 100 m long gently curved wall feature, located just southwest of West Mound. We wanted to examine if this was a prehistoric embankment. But the excavation showed that the formation is a result of extensive measures of the National Heritage Board from the 1920s onwards (Gustawsson 1949). Högåsen is the most prominent burial ground in the area, but it from an antiquarian perspective it was in a bad state. The National Heritage board eventually started a process where farms and houses on the burial ground were removed, graves were repaired and the landscape turned into the park we see today. We struck upon forgotten efforts from this restoration process as the wall feature was largely constructed from 20th century destruction debris. It is interesting that the early 20th century antiquarians wanted to create some kind of original state of the burial ground. But in this process they also added new features to the landscape.

Stripping of topsoil south of the royal mounds (Kungshögarna).

The second area includes anomalies from a magnetometer survey that two different rows of large postholes (Trinks & Biwall 2011). One row ran E-W and has been partially excavated due to the expansion of the railway line north of Uppsala (Beronius, Göthberg, Seiler & Wikborg 2013). Another 12 anomalies were interpreted as a second row, running N-S along the Högåsen burial ground.  Our excavation strengthened the survey results for the post row line running E-W. We have probably found its western end and in the process of stripping the topsoil, a new and previously unknown post foundation was found. This had not been captured by the magnetometer survey. The results from excavating the second row were totally different. A total of four anomalies were excavated. They consisted of a Migration Period hearth, layers of cultivation, a natural formation and the offprint of a removed boulder.

Posthole 549 associated with the E-W post row line.

This was the first time that larger surfaces were unveiled in the SW part of Gamla Uppsala. There were no traces of damaged graves in the area and only a few settlement related features. Graves cannot however, be ruled out in the area as the southern parts of the burial ground have been damaged by the plow. The area does not seem to be have been deep plowed. The nearest settlement from the early Iron Age is more than 400 m away, so the Migration Period hearth is interesting. Is it a form of activities in the outback of this period, or does it represent the edge of a settlement or even grave related activities from a phase where we still lack burials in this area.