The paleontological site Masol is located in the Himalayan foothills, north of Punjab (India), in the Chandigarh hills. The monsoon combined with tectonics have dug a 60-hectare inlier around a culmination of an anticline. Seasonal torrents release layers of silts and sands within an area rich in mammal and reptile fossils attributed to the late Pliocene (Sahni and Khan 1964, Badam 1973, Nanda 2013). Sahni and Khan have defined the Plio-Pleistocene boundary on sedimentary criteria (pebbles in sands). The torrents are drained by the rivulet Patiali Rao which flows into the Punjab plains. The magnetostratigraphy of its banks locates the fossiliferous layers below the Gauss-Matuyama Reversal (>2.58 Ma) (Ranga Rao 1993). The correspondence between the inversion and the pebbly sands had to be checked. Since 2009 our team surveys the fossiliferous layers (n = 1500 fossils) and collected herbivore bones with cut and percussion marks made by sharp edges in quartzite (Palevol, 2016, 15: 279-452). Their spatial organisation and their trajectories in the sectors of ligament and tendon attachments, enable to reconstitute the manual gestures. Quartzite pebbles have been observed for the first time inside the fossiliferous silts. In 12 localities, fossils have been collected with lithic artefacts (choppers, flakes, hammers, anvils, cores) on surface in permanent erosion. The lithostratigraphic study records 170 meters of sedimentary deposits from the bed of the rivulet Patiali Rao up to the crest that corresponds to the suspected Plio-Pleistocene limit. The fossiliferous layers of 50 meter thickness are located in the lower part of the sequence. The new geological and faunal studies (lithology, mineralogy, granulometry, taxonomy, taphonomy) attest to the fluvio-marshy environments formed by Himalayan rivers flowing into the paleoplains. The layers have restored terrestrial and aquatic vertebrates (e.g. Merycopotamus, Sivatherium, Bos, Hexaprotodon, Testudo atlas) along with assemblages typical of the Late Pliocene (Stegodon-Elephas and Hipparion-Equus) and a weak representation of predators (crocodiles, hyenas, Panthera). New magnetostratigraphic analyses were firstly performed at the locality where the oldest butchery activities had taken place, close to where a chopper was extracted in stratigraphy for the first time in 2017, and secondly at the highest sequence on the crest. The polarity is normal, invalidating the suspected Plio-Pleistocene lithological boundary (Chapon Sao et al., in preparation). The geomagnetic reversal is pushed higher in the stratigraphy beyond the crest. The pebbly sands are being dated by Electron Spin Resonance (UMR 7194) and by cosmonucleids (at CEREGE by GEOPS). The cut marks and the first chopper in situ at Masol 1 are 140 meters below these sands, the result of the dating will be presented and the implications discussed.