Building Materials of Neolithic Tombs in Alava, Northern Spain

Fifty-two Neolithic tombs (dolmens) were grouped into megalithic stations that are mostly located on lithotecto from which the building rocks were removed. In six dolmens, there were no clues found to explain the presence of allochthonous stones, except perhaps in one of them, where rocks were selected to cause colour contrast. The morphology of the slabs, of chambers and corridors, showed no evidence of carving. The angularity of the tumulus blocks indicates that some were collected from the surface and others were manually fragmented. The identification of the construction materials in Neolithic dolmens with elemental geological features provides information on the building process, adding valorisation to the prehistoric monuments and enabling their reconstruction.