and ships. During the Late Bronze Age and until 800-600 BCE the contacts with both southern Spain to the south, and Armorica and the Atlantic Isles to the north, intensified, probably fuelled by the abundance of local gold and metals such as tin, which allowed the production of high quality bronze. It is at this moment that began the deposition or hoarding of prestige items, frequently in aquatic context. Also, during the Late Bronze Age a new type of ceremonial henge-like ring structures, of some 50 metres in diameter, are built all along Galicia. This period and interchange network, usually known as Atlantic Bronze Age, which appears to have had its centre in modern-day Brittany, was proposed by John T. Koch and Sir Barry Cunliffe as the one that originated Celtic languages —as a product of pre-existing and closely related Indo-European languages— which could have expanded along with the elite ideology associated with this cultural complex (Celtic from the west theory). Alleged difficulties with this theory and with pre-existing theories ("Celtic from the east") have led Patrick Simms-Williams to propose an intermediate "Celtic from the centre" theory, with an expansion of Celtic languages from the Alps during the Bronze Age.<ref name="cambridge.org">An Alternative to 'Celtic from the East' and 'Celtic from the West''', Patrick Sims-Williams, Cambridge University Press, 2020 </ref> A recent study shows the large scale admixture of an earlier population from Britain with people arriving probably from France during the late Bronze Age. These people, in the opinion of the authors, constitute a plausible vector for the expansion of Celtic languages into Britain, as no further Iron Age people movement of relevant scale is shown in their data. The Bronze Age - Iron Age transition (locally 1000-600 BCE) coincides with the hoarding of large quantity of bronze axes, unused, both in Galicia, Brittany, and southern Britain. During this same transitional period, some communities began to protect their villages, settling in very protected areas where they built hill-forts. Among the oldest of these are Chandebrito in Nigrán, Penas do Castelo in A Pobra do Brollón and O Cociñadoiro in Arteixo, on a sea cliff and protected by a 3-metre-tall wall, it was also a metal factory, perhaps dedicated to the Atlantic commerce, all of them founded some 2,900-2,700 years ago. These earlier fortified settlements seem to be placed to control metallurgical resources and commerce. This transitional period is also characterized