The end of the Middle Pleistocene is an interesting period for investigating the transformation of Neandertal behavior from the early Middle Paleolithic to the late Middle Paleolithic. Few sites in the Iberian Peninsula have sequences corresponding to the last interglacial (MIS5) and even fewer in the Cantabrian Region. One of the best places to investigate this subject is the sequence recently excavated in Arlanpe cave. Several proxies (sedimentology, pollen, small vertebrates, malacofauna, U/Th dating) locate the first phases of this sequence between MIS7 and MIS5, with the important occurrence of temperate environmental evidence. The archaeological record describes populations with high mobility that used the cave as an occasional shelter in the first phases, or as an activity area in the later ones. The characteristics of lithic productions show a combination of Lower (Acheulean bifacial shaping) and Middle Paleolithic (Levallois Technology) traits that justifies an early Middle Paleolithic attribution.