Founded in the early Viking Age, Aarhus is one of the oldest cities in Denmark, along with Ribe and Hedeby. Achaeological evidence under the Aros settlement’s defences indicate the site was a town as early as the last quarter of the 8th century, considerably earlier than had been generally supposed.Discoveries after a 2003 archaeological dig unearthed half-buried longhouses, firepits, glass pearls and a road dated to the late 700s. Archaeologists have conducted several excavations in the inner city since the 1960s revealing wells, streets, homes and workshops. In the buildings and adjoining archaeological layers, everyday utensils like combs, jewellery and basic multi-purpose tools from approximately the year 900 have been found.
The centre of Aarhus was once a pagan burial site until Aarhus’ first church, Holy Trinity Church, a timber structure, was built upon it during the reign of Frode, King of Jutland, around 900. In the 900s an earth rampart for the defence of the early city was constructed, encircling the settlement, much like the defence structures found at Viking ring fortresses elsewhere. The rampart was later reinforced by Harald Bluetooth, and together with the town’s geographical placement, this suggests that Aros was an important trade and military centre. There are strong indications of a former royal residence from the Viking Age in Viby, a few kilometres south of the Aarhus city centre.