Single Grave culture  The Single Grave culture () was a Chalcolithic culture which flourished on the western North European Plain from ca. 2,800 BC to 2,200 BC. It is characterized by the practice of single burial, the deceased usually being accompanied by a battle-axe, amber beads, and pottery vessels. The Single Grave culture was a local variant of the Corded Ware culture, and appears to have emerged as a result of a migration of peoples from the Pontic-Caspian steppe. It was succeeded by the Bell Beaker culture, which appears to have been ultimately derived from the Single Grave culture. The Single Grave culture was an offshoot of the Corded Ware culture, which was itself an offshoot of the Yamnaya culture of the Pontic-Caspian steppe. On the western North European Plain, the Single Grave culture replaced the earlier Funnelbeaker culture. The Single Grave culture came to encompass the western part of the European Plain. In Denmark, Single Grave sites are concentrated in Jylland, where its appearance is accompanied by large-scale forest clearance and an expansion of animal husbandry, particularly cattle. In eastern Denmark, the Single Grave culture, the Pitted Ware culture, and the Funnelbeaker culture appear to have co-existed for some time. It maintained close connections to other cultures of the Corded Ware horizon. The Single Grave culture was succeeded by the Bell Beaker culture. The Bell Beaker culture is thought to have been derived from the Protruding-Foot Beaker culture (PFB), which was a variant of the Single Grave culture. The term "Single Grave culture" was first introduced by the Danish archaeologist in the late 1800s. He found Single Graves to be quite different from the already known dolmens, long barrows and passage graves. In 1898, Danish archaeologist Sophus Müller was first to present a migration-hypothesis stating that previously known dolmens, long barrows, passage graves and newly discovered single graves may represent two completely different groups of people, stating "Single graves are traces of new, from the south coming tribes". The Single Grave culture is known chiefly from its burial mounds. Thousands of such mounds have been discovered. These are typically low, circular earthen mounds. Originally, the mounds were surrounded by a circle of split timbers. In low mounds, grave would contain one, or even two, plank coffins. Each coffin contained a single individual.