The site of Goulet “Le Mont” was discoverd during the archaeological survey preceding the construction of A88 highway between Caen and Sées. It is located near Argentan on the first plates dominating the Orne, which flows a few hundred meters away, and surmounts one of its affluent, the Houay. The site is established on the slope of this valley. It is marked by sections of ditches of 10 to 50 metres long, which draw a vast enclosure, whose diameter is gauged to be 550 metres, according to results of the excavation, aerial photographies and geophysical prospecting. This sums up to 1,7 kilometre of ditch and an internal surface of around 20 hectares. Within the excavation, only the western part of this structure could be observed. The ditches were dug in the calcareous substrate. Parts of the ditch located at the western end are no more than thirty centimetres under the level of scouring (0,70 metre under the surface of the ground) while the others can be as deep as 1,30 or 2 metres under this same scouring. The furniture discovered within the ditch is not very common. It is attached to middle Neolithic II, between 4400 and 3600 BC according to the absolute datings. The filling of the structure allowed the construction of a pollinic transept which revealed a significant impact of cereal growing in the close surroundings of the enclosure.