In 2000, the Atapuerca Research Team (ART) began an archaeological survey of prehistoric campsites around the caves. Nearly 200 open-air settlements were documented, 30 of which date back to the Middle Palaeolithic, when Europe and Atapuerca in particular were inhabited by Neanderthal groups.
Four of the Neanderthal campsites in the Sierra de Atapuerca (Valle de las Orquídeas, Hundidero, Hotel California and Fuente Mudarra) have now been excavated. Their chronologies range from 70,000 to 40,000 years ago. They shed light on the everyday lives of these hunter-gatherer groups, who disappeared without a trace not long afterwards.