Notarchirico (Southern Italy) has yielded the earliest evidence of Acheulean settlement in Italy and four older occupation levels have recently been unearthed, including one with bifaces, extending the roots of the Acheulean in Italy even further back in time. New 40 Ar/ 39 Ar on tephras and ESR dates on bleached quartz securely and accurately place these occupations between 695 and 670 ka (MIS 17), penecontemporaneous with the Moulin-Quignon and la Noira sites (France). These new data demonstrate a very rapid expansion of shared traditions over Western Europe during a period of highly variable climatic conditions, including interglacial and glacial episodes, between 670 and 650 (i.e., MIS17/MIS16 transition). The diversity of tools and activities observed in these three sites shows that Western Europe was populated by adaptable hominins during this time. These conclusions question the existence of refuge areas during intense glacial stages and raise questions concerning understudied migration pathways, such as the Sicilian route. Recent data in prehistory tend to break down the previously supposed clear boundary between anatomically "modern" humans (Homo sapiens), associated with modern cognitive abilities, and earlier hominin species, such as Neanderthals and their ancestors, Homo heidelbergensis. The earliest Acheulean Homo heidelbergensis groups arrived in Europe ca. 1.0-0.7 Ma ago, and were exposed to challenging environmental conditions, which may have stimulated new cultural responses. These included behavioral innovations that could have potentially derived from African or Levantine origins during these early time ranges. During this period, named the Mid-Pleistocene revolution, Northern Europe was characterized by constraining climatic conditions, especially during glacial stages (1.25-0.7 Ma). Major topographic and sea-crossing barriers constituted considerable challenges