New research on dating this dolmen published (in Spanish) at https://www.academia.edu/30700948/Pasados_rele%C3%ADdos_el_dolmen_del_Portillo_de_las_Cortes._Guadalajara_MAN.
Positive results have been obtained from resuming the study of the dolmen of El Portillo de las Cortes (Guadalajara, Spain) taking into account materials that are nowadays kept in the MAN (Museo Arqueológico Nacional) as well as recent fieldwork. We hereby present a new C14 date obtained from a recently found and documented skull from the MAN, and new perspectives about possible ancient interventions to rebuild the monument and about supply sources for the community that erected it.
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