This site boasts the largest burial mound in Sweden (14m high and 60m in diameter at the base), probably built between 400 and 700. The two lines of stones forming a double ship, 53m and 50m long respectively, as well as three smaller line date from the year 1000. During the Middle Ages, the site became the meeting place for the people's assembly (tingvalla). The king, travelling between Västerås and Uppsala, would arrive by the old road, Eriksgata, which is lined with rune stones and rows of smaller stones.