Tumulus culture
Italic and Celtic languages are commonly grouped together on the basis of features shared by these two branches and no others. This could imply that they are descended from a common ancestor and/or Proto-Celtic and Proto-Italic developed in close proximity over a long period of time. The link to the Yamnaya-culture, in the contact zone of western and central Europe between Rhine and Vistula (Poland), is as follows: Yamnaya culture (c. 3300–2600 BC) - Corded Ware culture (c. 3100-2350 BCE) - Bell Beaker culture (c. 2800–1800 BC) - Unetice culture (c. 2300-1680 BCE) - Tumulus culture (c. 1600-1200 BCE) - Urnfield culture (c. 1300-750 BCE). At the Balkan, the Vučedol culture (c.3000-2200 BCE) formed a contact zone between post-Yamnaya and Bell Beaker culture.