Fossilised teeth, Gran Dolina. These human teeth, dating back approximately 800,000 years, were found in level TD6 at the Gran Dolina site between 1994 and 1995. In total, 80 human fossils belonging to a least six individuals, ranging from the young to the old, were recovered. This find led to the naming of a new human species, Homo antecessor. Gran Dolina is one of several archaeological sites in Sierra de Atapuerca, Spain, that have been studied on and off over the past century, leading to a massive advancement in the understanding of human evolution. In 2000, Sierra de Atapuerca was made a world heritage site by UNESCO.