Alto de Reinoso megalithic tomb is a Neolithic collective burial that had been used approximately one hundred years around 3700 cal BC.
See:
- Kurt W. Alt at all. A Community in Life and Death: The Late Neolithic Megalithic Tomb at Alto de Reinoso (Burgos, Spain), 2016 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4720281/
- http://www.anthrogenica.com/showthread.php?6299-A-Community-in-Life-and-Death-The-Late-Neolithic-Megalithic-Tomb-at-Alto-de-Reinoso