The Aggersborg viking fortress - a part of UNESCO's World Heritage List

Aggersborg is located at Aggersund in the northwestern corner of Himmerland and is clearly the largest of Denmark's five viking fortresses. Along with the four other fortresses, Fyrkat, Nonnebakken, Trelleborg, and Borgring, Aggersborg was included in UNESCO's World Heritage List in September 2023.

The history of the fortress

Aggersborg is both the oldest and the largest of the Viking Age ring fortresses and must have been an impressive sight, especially from the fjord. A massive structure with ramparts and palisades clad in timber. The fortress was built by Harald Bluetooth in the late 970s and consisted of a 9 m wide and approximately 4 m high circular rampart, pierced by four gates oriented according to the cardinal directions. The inner diameter of the fortress was 240 meters, and within the fortress, two wooden-paved streets connected the gates and met at right angles in the center of the complex.

Built on a hillside at one of the narrowest points of the Limfjord, it stood out prominently in the landscape as a massive structure with a total of 48 longhouses within the ramparts and an inner diameter of 240 meters. Aggersborg stands out by being twice as large as the four other ring fortresses, which is likely due to its strategic location at the then most important traffic artery, the Limfjord. Traffic and trade between east and west, north and south, could be controlled from the fortress.

Even before the fortress was built, there was a lively trading place with a prominent chieftain's estate dating back to the 8th century. After the abandonment of the ring fortress, the area became a royal estate. After the decay of the ring fortress, the area remained in the hands of royal power, and a royal estate emerged. Today, the current protected manor, Aggersborggård, represents the last part of Aggersborg's long history. Aggersborg and Vesthimmerland are connected with the history of the power landscape in the Viking Age. Archaeological finds from the area show the region's close connection to royal power and the wealth of trade associated with the Limfjord.

Guided Tour

Be transported back to the Viking Age with an exciting guided tour at Aggersborg. Vesthimmerlands Museum arranges several tours throughout the year, where you can hear fascinating stories about Harald Bluetooth, kings, Vikings, and their daily lives. Read more here and book your place today!

Tours can be booked in both Danish and English.

Fun for Kids

The youngest visitors at Aggersborg are also considered, as a guided tour might not be their idea of fun. That’s why Aggersborg has developed the activity booklet "The Children's Castle," where your family can help King Harald Bluetooth and test your skills as Vikings. If all goes well, you might end up with a royal certificate proving you're true Aggersborg Vikings.

The booklet costs 50 kroner and can be purchased from the guides at the castle.