Fyrkat Viking Fortress was constructed in 980 during the reign of King Harald Bluetooth. None of the original five ring fortresses known today still exist, but at Fyrkat, an earthen rampart marks the area where the fort once surrounded the original 16 farmhouses. The locations of these houses are now indicated by white stones.

Just outside the fortress, one of the longhouses has been reconstructed.

King Harald Bluetooth’s Ring Fortresses

In addition to the Viking fortress Fyrkat, Denmark is home to four other ring fortresses – the most recent being Borgring near Køge, discovered in 2014. The others are Aggersborg near Løgstør, Trelleborg near Slagelse, and Nonnebakken in Odense. Although they vary in size, they share such a similar construction and design that there is no doubt they have the same origin. Tree-ring dating of the woodwork indicates that they were built around 980, and thus, it can be reasonably concluded that they were associated with King Harald Bluetooth.

These mighty forts, built with great skill, engineering prowess, and at enormous cost to both the population and the royal authority, played a central role in Danish history in the late 10th century.

Harald Bluetooth held his land in an iron grip, and the ring forts were part of the strategy devised by the king and his master builder to unite Denmark. The lifespan of these forts was short – just under 20 years. Fyrkat was destroyed in a severe fire, and mass graves near Trelleborg confirm that battles took place at the fortresses.