Sima de los Huesos

The Sima de los Huesos, or "Pit of Bones," is a cave located in the Atapuerca cave system in northern Spain. This site has yielded an astonishing collection of over 1,600 human fossils, making it the largest hominin fossil find in the world. The remains found here are at least 300,000 years old, and possibly as old as 600,000 years.1

These fossils belong to the species Homo heidelbergensis, which is considered a direct ancestor of Neanderthals. The brain sizes of these individuals fall within the range of both Neanderthals and modern humans. Unique Neanderthal traits, such as a projecting midface and long pubic bones, are present in the skeletons, though not fully developed as in later Neanderthals. The site also contains evidence of interpersonal violence, with a 430,000-year-old fractured skull found there. Atapuerca was designated a UNESCO World Heritage site in 2000.1