Nydam Mose ("Nydam Bog") is an archaeological site located at Øster Sottrup, a town located in Sundeved, eight kilometres from Sønderborg, Denmark.
In the Iron Age, the site of the bog was a sacred place, where the weapons and ships of vanquished armies were offered to the indigenous gods in thanks for victory over the fallen enemy. Many items were deliberately destroyed (bent, broken or hacked into pieces) in ritual sacrificial acts, from the period 200 to 400 AD. Nydam Bog has played a role in the Danish national claim for Southern Jutland.
The first known finds from the bog date from the 1830s, when a local farmer gave old swords and shields as toys to his children.
Amongst numerous other items, three boats were found in Nydam Bog. In particular, the 23 metre long oak boat, commonly known as "the Nydam Boat", maintains a distinguished position amongst Danish Iron Age finds, as it is the oldest known rowing vessel in Northern Europe. The oak (egetræsbåden) boat is on display at the archaeological museum in Gottorp Castle, Schleswig, Germany.
From 1859 to 1863, archaeologist Conrad Engelhardt excavated the bog. Engelhardt found weapons, tools, pieces of clothing and two intact clinker built boats, one made of oak and one made of pine. The weapons include lances, spears, bows, arrows and round shields. Under these finds were the remains of a third boat, which apparently had been demolished already during the sacrifice.
Engelhardt’s work ceased with the outbreak of the Second Schleswig War in early 1864. Some of the discoveries from the bog were lost during the Second Schleswig War. The smaller of the two boats, perhaps 19 meters long and made of pine, was hacked up and used as firewood by troops.