Neanderthal excavation. Researchers carrying out excavations for prehistoric human fossils at the Pinilla del Valle site, in the Lozoya Valley, near Madrid, Spain. Several Neanderthal fossils have been found here. Neanderthals (Homo neanderthalensis) inhabited Europe and western Asia between 230, 000 and 29, 000 years ago. They did not use complex tools but had mastery of fire and built shelters. It is thought that they had language and a complex social structure, living in small family groups and hunting for food. Excavations by around 70 people have been taking place here every summer for over a decade since around 2002. Photographed in September 2015.