Raknehaugen

Rakni's Mound (Norwegian: Raknehaugen) in Ullensaker is the largest free-standing prehistoric monument in Norway and one of the largest barrows in Northern Europe. It dates to the Migration Age and has been the subject of three archaeological investigations.

The mound is 77 metres in diameter and over 15 metres in height, the largest in Scandinavia.Carbon-14 dating in 1956–57 (the first use of the technique in Norway) dated its construction to the Migration Age, between 440 and 625. Later research has refined this to the mid-6th century, probably between 533 and 551.

It is located next to a small lake or pond near where the old road from Lake Mjøsa to Oslo and the road to Nannestad meet, probably the centre of an ancient chiefdom. The farm, which is mentioned in records from the Middle Ages, is called Ljøgodt from Ljoðgata (Old Norse for "main track"); another nearby farm, also mentioned in medieval sources, is called Haug (from Old Norse haugr "hill; mound") after the mound. The great mound was surrounded by smaller, later burials until the early twentieth century; aerial photographs show the outlines of more than 30 now effaced mounds, and archaeological digs have dated burials between the 7th century and the Viking Age. They were mostly simple cremations with few grave goods, and three are in the trench around the mound itself.

The mound was raised over three cone-shaped layers of approximately 75,000 stacked logs from 30,000 trees, on which were heaped some 80,000 cubic metres of sand taken from trenches around the mound, clay and soil.Dendrochronology and carbon-dating show 97% of the trees were felled in a single winter, in 533–551. The construction has been estimated to have required the work of 40–50 people felling trees the winter before the mound was built, followed by 450–600 over the summer to build it; or 160–200 men working for 150 days. The trees were quite homogeneous, none over 60 years old, and had been grown in open woodland, providing the first evidence of large-scale forestry in Iron Age Scandinavia. Traces of ancient agriculture and cooking pits, which predate the mound, lie under it.

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