Nobody can say for certain who first dug the northern end of the Danevirke, but the best evidence points to a king named Godfred. The Frankish chroniclers record that in the year 808 this Danish ruler, a rival of Charlemagne, ordered a great wall built across the neck of the peninsula to protect his kingdom from Frankish attack. Tree-ring dating of timbers from the early rampart has found wood felled in the 730s, so the story is older and more complicated than a single king, but Godfred's name is tied to the Danevirke, and he is also linked to the founding of the trading town of Hedeby nearby.
This section combines two parts of the system, a connection wall and the North Wall, and the North Wall is the oldest and the most northerly of the barriers. In its first form it was a timber palisade behind a ditch, with earth heaped up behind it and a gate for the main road. Over the centuries it was lengthened and strengthened, and later kings added new walls and ditches, so that what you see today is a layer cake of building phases.
The place is at its best in the quiet of early morning, when mist lies on the fields and the bank looks like a long green wave. There are marked paths and a few information boards, though much is left to the imagination. Roads around Dannewerk are narrow and little used, and you can usually park at the roadside near the footpath.
Dannewerk is a village of a thousand people and has little for the traveller beyond a pub or a bakery, while Schuby offers a few shops. For fuel and a proper lunch go on to Schleswig, about four kilometres off. The ground is dry and sandy, a gift to walkers, though it can be boggy after heavy rain. Wear sturdy shoes, bring some water, and give yourself half an hour to follow the rampart through the trees. It is the nearest thing to meeting a Viking king in person.