Hedeby (Danish pronunciation: [ˈheːð̩byːˀ], Old Norse Heiðabýr, German Haithabu) was an important Viking Age (8th to the 11th centuries) trading settlement near the southern end of the Jutland Peninsula, now in the Schleswig-Flensburg district of Schleswig-Holstein, Germany. It is the most important archaeological site in Schleswig-Holstein.