Evidence for human occupation of the Zagros reaches back into the Lower Palaeolithic, as evidenced by the discovery of many cave-sites dating to that period in the Iranian part of the mountain range. Middle Palaeolithic stone tool assemblages are known from Barda Balka, a cave-site south of the Little Zab; and from the Iranian Zagros. A Mousterian stone tool assemblage – produced by either Neanderthals or anatomically modern humans – was recently excavated in Erbil. Neanderthals also occupied the site of Shanidar. This cave-site, located in the Sapna Valley, has yielded a settlement sequence stretching from the Middle Palaeolithic up to the Epipalaeolithic period. The site is particularly well known for its Neanderthal burials. The Epipalaeolithic occupation of Shanidar, contemporary with the use of the Kebaran stone tool assemblage, is the oldest evidence for anatomically modern human occupation of the Great Zab basin. The following Protoneolithic, or Natufian, occupation is contemporary with the oldest occupation of the nearby open-air site Zawi Chemi Shanidar. M'lefaat on the Khazir River (a tributary to the Great Zab) was a small village of hunter-gatherers dating to the 10th millennium BCE that was contemporary with the Pre-Pottery Neolithic A in the Levant. An archaeological survey of the Citadel of Erbil, in the plain south of the lower course of the Great Zab, has shown that this site was continuously occupied at least from the 6th millennium BCE upward.