Aggersborg

Aggersborg is the largest of Denmark's former Viking ring fortress, and one of the largest archaeological sites in Denmark. It is located near Aggersund on the north side of the Limfjord. It consists of a circular rampart surrounded by a ditch. Four main roads arranged in a cross connects the fortress center with the rampart's outer ring. The roads were tunneled under the outer rampart, leaving the circular structure intact. Many archaeological excavations have been conducted on the site, revealing its original structure and design. These excavations also uncovered a large number of artefacts from the Iron Age and Viking Age. The surface of the site as it exists today is a reconstruction.

The location was originally the site of an Iron Age village which was removed during the 10th century to allow for the construction of the ring fortress. The fortress itself was likely constructed c. 980, and was later abandoned. Although the exact purpose of the fortress is unknown, the location is of significant strategic importance, as it overlooks a narrow strait of the Limfjord. In 2023, Aggersborg, along with four other ring fortresses in Denmark, was inscribed on the UNESCO World Heritage List.