Archaeologists in Sweden said Thursday they have unearthed the remains of unusually large wooden monuments near a pre-Viking Age burial ground.
As archaeologists dug in preparation for a new railway line, they found traces of two rows of wooden pillars in Old Uppsala, an ancient pagan religious center. One stretched about 1,000 yards (1 kilometer) and the other was half as long.
Archaeologist Lena Beronius-Jorpeland said the colonnades were likely from the 5th century but their purpose is unclear. She called it Sweden's largest Iron Age construction and said the geometrical structure is unique.