The Danevirke is a wall, or rather a series of walls, that once stretched across the neck of the Jutland peninsula, and this stretch is the eastern end, near the Windeby lake and the shore of the Baltic. The first earthworks went up in the seventh century, and later kings of Denmark extended them in several phases, culminating in a brick-faced wall built in the twelfth century under Valdemar the Great. The purpose was to protect the southern border against the Franks and the Saxons, and it worked more or less for several hundred years. A few steps along the grassy bank, and you can see a low ridge and a ditch, easily mistaken for a hedgerow.
Hedeby, the great Viking trading town at the end of the Schlei inlet, lay just behind the wall and was one of the largest settlements in northern Europe in the ninth and tenth centuries, with merchants, craftsmen and ships from Scandinavia to the Arab world. UNESCO lists the wall and the town together as the Archaeological Border Complex of Hedeby and the Danevirke, and a museum near the site shows reconstructed Viking houses and a warship. Windeby, a village nearby, is known for a bog body, a young person from the Iron Age found in a peat bog in 1952 and long called the Windeby Girl, though more recent research has made the identification uncertain.
The riding is gentle. The roads around Eckernförde and the Schlei run through rolling farmland, with fields of rapeseed and wheat, dark beech woods and brick-built villages with thatched roofs, and the Baltic is never far. The surface is generally good, and the traffic is light outside the holiday season. Wind from the sea can be strong, particularly in spring and autumn, and sudden showers are likely at any time of year. Look for storks in the villages in summer and for wild geese in winter.
Eckernförde, with about twenty-three thousand people four kilometres away, has fuel, bakeries and fish restaurants, and its harbour is a pleasant place for a coffee. Try a smoked sprat, a local speciality, or a fish roll from a stall. Summer weekends are busy with holidaymakers, and midweek is calmer. The best times are late spring and early autumn, when the light is golden, and winter brings a cold, grey beauty to the whole coast.