Arras was founded on the hill of Baudimont by the Celtic tribe of the Atrebates, who named it Nemetacum or Nemetocena in reference to a nemeton (sacred grove) that probably existed there. It was later renamed Atrebatum by the Romans, under whom it became an important garrison town. The archaeological site Nemetacum in Arras is one of the rare sanctuaries devoted to the oriental god Attis in France.
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