This page concerns the prehistory of Brittany. Palaeolithic Brittany was never glaciated during the Quaternary, owing to its latitude, proximity to the coast and absence of significant mountain ranges. However, even though free of glaciers, Palaeolithic Brittany was extremely cold compared to its present climate, with annual mean temperatures at the last glacial maximum estimated at -3 °C (27 °F). Permafrost was present with only a very shallow active layer estimated at only 1 foot (30 cm) thawing each summer, so that only a very light (less than 5 percent) cover of tundra could grow. This vegetation could only support very low densities of grazing mammals like reindeer, which (in Europe) are found today only in areas then uninhabitable due to the presence of thick ice sheets. Consequently, few if any people could survive in Brittany prior to the end of the last glaciation, and only a few Palaeolithic sites are known from Brittany, like the rock shelter of Perros-Guirec near Rochworn. The only cave site known so far is Roc'h Toul in a sandstone promontory near Guiclan (Finistère). The cave contained about 200 artifacts and was dated to the late Magdalenian by de Mortillet. Because of the presence of points with curved backs, it is now connected with the epipalaeolithic Azilian. Other Azilian sites include Parc-an-Plenen and Enez Guennoc. Mesolithic The best-known mesolithic sites from Brittany are the cemeteries on the islands of Hoëdic (10 graves) and Téviec (9 graves) in Morbihan. The collective graves are placed in shell middens without any particular order. Some graves show evidence of postmortal manipulations of the bones. There are single burials and empty graves (cenotaphs) as well. The graves are covered with stones, a hearth or antlers forming a sort of dome. Rich funeral gifts, flint tools, engraved bones, shell ornaments and ochre demonstrate the affluence of these hunter-gatherers, or rather fisher-gatherers. Certain shells are sex-specific. In Teviec there are stone cist graves. The bones of an infant have been postmortally ornamented with striations. The corresponding settlements consist of shell middens. A radiocarbon date of 4625 (uncal.) for Hoëdic places it in the 6th Millennium BC cal, rather late in the Mesolithic sequence, and indeed there are some indications of contact with agricultural societies to the East. Their economy was based on marine resources. Recently, a number of accelerator dates have been published for Hoëdic. In Beg an Dorchenn in Plomeur (Finistère),