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West Kennet Long Barrow (England)

West Kennet Long Barrow was built around 3650 BC.Some cremations and the partial remains of at least forty-six individuals – both male and female and of all ages – have been found inside, together with grave goods including pottery, beads and stone implements such as a dagger, dated to between 3000 and 2600 BC.The barrow was first excavated in 1859 and then again, scientifically, in 1955–6, after which the site was restored and the façade and chambers at the eastern end reconstructed. (English Heritage)

 http://www.avebury-web.co.uk/wk_lbarrow.html

Carreg Hirfaen Menhir (Wales)

Crug-ybiswal Round Barrow (Wales)

Pentre Ifan Burial Chamber (Wales)

Trefach Menhir (Wales)