Atapuerca is a small municipality located 18 kilometres away from Burgos, on the northern slope of Sierra de Burgos, famous for the prehistoric archaeological sites found in its township. Declared a World Heritage by UNESCO on November 30th, 2000, the archaeological sites of Sierra de Atapuerca are the only ones in Europe where it is possible to follow the evolution of the first human beings to inhabit the Old Continent, from approximately a million years ago to very recent periods. The history of Atapuerca began in 1899, when the construction of a railway unveiled several archaeological sites. But it was not until the 1960s that the most relevant research began, thanks to the Edelweiss spelaeology group, which worked as a catalyst for it to happen. This group pointed out to mining engineer Trinidad Torres where to find cave bear bones, information he needed in order to complete his doctoral thesis. But when they began digging, they discovered very ancient human bones at Cueva Mayor (High Cave). Palaeontology professor Emiliano Aguirre analysed and confirmed these findings, in what constituted the first step towards a great scientific research project that began in 1978, and continues today. The finding of important human remains during the 1990s brought fame to Atapuerca, and allowed for a deeper understanding of human evolution.