The ten metre-long Riparo del Broion is protected by an outcrop of circa 7 m and contains a fill that was partially removed in order to level the surface for agricultural use. The surface was cut some years ago by an illegal excavation, over a total surface area of 14 m2, to a depth of 2m. In 1998 systematic excavations began which revealed a stratigraphy in which 16 distinct units have been identified, the lowest of which (13, 9, 7 and 4) containing artefacts of the Middle Paleolithic. The overlying levels contained artefacts of the Upper Paleolithic. Levels 3 and 2, investigated over a surface of 8 m2, produced no traces of anthropological evidence.

The upper layer 1, circa 80 cm thick, had a clearly defined lower edge and was subdivided into seven sub-layers (1g – 1a) almost all of which clearly distinct. Up against the rock face the sediments were incoherent, some effected by erosion and animal burrows. Two hearths (1g and 1f) dated to the early part of the Upper Paleolithic. In the central sector of the excavation a sub-circular structure S2, diameter of 50 cm, depth 8 cm, cut into layer 2. The fill comprised a fine sediment with an abundance of organic material, small clasts, occasional charcoal, burnt bones and some flint artefacts that showed signs of burning. The C14 (AMS) dating for this material is 32.100±400 (UtC-11.790), 25.980±190 (UtC-11.791), 30.480±300 (UtC-11.792) BP. In the western sector, structure S3, cutting layer 2, was constituted by a sub-circular depression 80 cm wide and 10 cm deep, surrounded by five lumps of local limestone. The depression was filled with silts rich in organic materials, with some charcoal, one piece of which dated to 31.700±400 (UtC-12.509)BP. The interface 1f/1g was dated 30.650±300 (LTL-1637A) BP. The extremely fragmentary faunal remains included among the carnivores the cave bear, common fox and wild cat; among the ungulates boar, elk, deer, roe deer, chamois; among the rodents and lake dwellers, hare and beaver. The remains of fish and marsh birds were also present. The assemblage suggests a marshy environment at the foot of the hills surrounded by forests with ample clearings.

The assemblage of lithics from 1g and 1f are attributed to the early part of the Upper Paleolithic. The flint used came from the Biancone and Scalglia Rossa formations, with the exception of an allocthonous flint blade. All phases of working were present; the production phase was represented by a few blade fragments. The cores had been exploited to the extreme, and all presented flaked detachments. In 1g there were three flat scrapers, three retouched blades, two backed knife blades; in 1f a retouched blade cf. Aurignacian blade, one curved backed knife cf. Ulzziano and two flaked fragments, one with direct and alternating edge retouch , were present. There were also one small piercer and a punch, both made from pieces of bone, and four shells (3 from the sea and 1 freshwater) used as personal ornaments, as attested by the clear traces of red ocra inside them. Two occupation phases were identified for the middle Upper Paleolithic in sub-layer 1c and 1b for which four C 14-AMS dates were obtained: 25.860±200 (UtC-13321) BP from sub-layer 1c and 27.960±300 (UtC-10.504), 17.830±100 (UtC-10.506) and 28.460±260 (UtC-260) BP relating to 1b. The date UtC-10.506 was given by a sub-circular hearth, 1 m in diameter and 7 cm deep (S1). The scarce faunal remains comprised cave bear, abundant marmot, goat, ox, fox, mustelids, birds and fish. Sub-layers 1e – 1a produced a Gravettian sequence within which it seemed possible to distinguish: a scarce assemblage (1e, 1d, 1c), perhaps attributable to the Gravettian period (on the basis of the radiometric dating relating to sub-layer 1c); an early Gravettian assemblage of backed points and rare leaf points (1b, 1b alfa, 1b beta e 1b gamma) for which two radiometric dates were obtained. This assemblage was notably homogeneous.

The implements were rare (two burins, one frontal scraper, one point, some re-touched blade fragments). Weapons were well represented, even though almost all fragments or residual: small, long, thin points of La Gravette facies, characterised by bipolar backs and complementary re-touches at the tip or base opposite the back; backed and truncated flakes. Lastly, of note the presence of a mesial fragment from a leaf point with a flat, narrow, long face, obtained by bilateral re-touching on the back and flat partial re-touching on the ventral face. A similar fragment came from the fill of a burrow together with other Gravettian artefacts. The lithic assemblage from the sub-layers overlying 1aα is consistent with this picture. The analysis of the traces of use revealed the points had been used as throwing weapons or as elements of composite tools used for cutting or sawing.