Torsburgen was an ancient fortress on the Baltic Sea island of Gotland belonging to Sweden. It was originally constructed at the beginning of the 1st century AD later reinforced during the 4th century and was in use until c. 1100 AD. A timber-laced stone rampart encircles an area of 12 hectares. Scholars estimate that nearly 1000 soldiers would have been needed to defend it [1] and it could have been providing refuge to the entire population of Gotland that is calculated to be between 6,000 and 10,000 in the early medieval period.