The excavation of the prehistoric site of Passo Pramollo is situated in the locality of Dosso Confine, on the north bank of the lake near the Austrian border, in correspondence with boundary stone P69. In 2003 a rock crystal artefact was found by a large boulder on this rise. In 2004 the area specialising in the rock crystal working was identified and several dozen artefacts were collected. Moreover, it was noted that proceeding to the south where the rise reached its peak, the crystals notably decreased in number, whilst the presence of flint was noted instead. Excavations in 2005 revealed that on top of the rise there was an area used only for flint flaking, attested not only by the abundance of material, but also by the presence of cores, implements, flakes and micro-flakes from retouching. The lithic material was mostly constituted by artefacts made of flint and hyaline quartz, which originated on the northern slope of the border watershed. Amongst the implements found, as well as cores, scrapers, retouched erto flakes, there were also microlithic back points, triangles, back blades and croppings, which provided a better chronology for the site placing it within the early Mesolithic (Sauveterrian) period. The station of Dosso di Confine documents the earliest phases of human occupation in the mountains of Friuli after the Würm glaciation. The site can be interpreted as a seasonal camp for Mesolithic hunters who went up into the mountains in the summer. The primary materials indicate that these groups may have travelled from nearby Austria. Moreover, the archaeological investigations revealed that the rise was also in use during the Roman (there were hearths of this date) and medieval periods. (MiBAC)