Rauðúlfs þáttr is a short allegorical story preserved in Iceland in a number of medieval manuscripts. The author is unknown but was apparently a 12th–13th century ecclesiastical person. The story is about Saint Olav's (Olav Haraldsson II king of Norway 995–1030) visit to a wise man named Rauðúlfr (also called Rauðr and Úlfr), their entertainment in the evening, the staying overnight in a round, rotating and richly decorated house and a vision the king had in his dream that night. The story is sometimes incorporated in the Separate Saga of St. Olaf. The visit The story relates King Olav's trip with his retinue, including the queen and bishop, to “Eystridalir” (now Österdalen) a then rather remote part of Norway, bordering on Sweden. He visits Rauðúlfr and his family who have been accused of cattle theft. Rauðúlfr and his two sons, Dagr and Sigurðr, turn out to be wise men, skilled in astronomy, time reckoning and physiognomy among other things. There is a feast in the evening where the king asks the bishop and six noblemen together with their host to relate about their skills, which they do one by one. After that the king and his retinue are led to a new house in the yard to spend the night. The rotating house The geometry and ornaments of the house are described in detail. The house was round, with four doors placed equidistantly. The roof had a dome, supported by twenty pillars. The house was divided into four quarters (presumably by corridors leading from the doors to the centre). The house was also divided in three concentric parts: a round central platform with steps and two outer parts divided by a fence. The central platform had a large bed where king Olav was to sleep. The bedposts had large spheres of gilded copper and projecting iron bars, each supporting a tripartite candle. The king's retinue was ordered by rank as follows. The queen was in the quarter on his left side with her ladies in waiting. The bishop was in the quarter on his right with the clerics. Three noblemen were in the quarter above the king's head, but three others in the opposite quarter. Twenty people slept in each quarter in the inner ring, but forty in the outer ring, 200 people altogether. As the king lay in the bed, he observed that the ceiling was all decorated with