Several dozen rural forging mills were discovered during research into settlement patterns in the Haut-Auxois around Alesia ( Alise-Sainte-Reine, Côte-d’Or ) and a village close to the “Source de la Seine” (Blessey– Salmaise). Chemical analyses and metallographic tests refined the discriminatory criteria, making it possible to define the work carried out in these forging mills : purification of imported raw metal and development of objects for the forging mills in the agglomerations ; development of objects only for the forging mills of the isolated rural settlements. The percentage of forging mills established along transport routes is exceptional. The Mandubian Haut–Auxois thus provides a still rare example of a thoroughly investigated area of small-scale rural iron and steel production. It occupies the eastern margins of a primary production region (the reduction of iron ore) which stretches from North Morvan to the Yonne and the Nièvre, forming one of the main iron and steel areas in Roman Gaul.