In September 2009 an archaeological survey was conducted by the author in one of the most mountainous provinces of Iran: Chahar Mahal va Bakhtiari (Figure 1, Roustaei 2009). The province is located in the southern half of the Zagros Mountains range in an area known as 'the roof of Iran' due to its high average altitude (Figure 2).
The name of this province stems from the name of one of the largest tribal confederacies of Iran, Bakhtiari, whose territory encompasses a vast area, both in the lowland Khuzistan province and in the inner highlands of the Zagros Mountains. The outstanding geomorphologic feature of the province is Zard Kuh (Yellow Mountain), a continuous chain of peaks more than 4000m in elevation — the highest reaches to 4221m (Figure 3). This impressive rock wall divides the immediate landscape into two ecological zones with distinct features: the Bazoft area to the west with rather dense forests of oak, steep-walled gorges, a good variety of wild life (including leopard, bear, boar, wolf, fox and other mammals and birds); and the high altitude Kuhrang area to the east with vast pastures and poor tree covering. Zard Kuh is famous for its numerous high discharge springs which feed two of the largest perennial rivers of Iran: the Karun River which flows to the west/south-west and, after passing through lowland Khuzistan, pours into the Persian Gulf; and the Zayande Rud which flows east, and, after irrigating the Isfahan Plain, ends in the Gav Khuni marsh in the central deserts.


The province has several districts; our survey area covers the highest district, Kouhrang, with an altitude of at least 2000m asl (Figure 2). It lies in the north-northwest of the province and is one of the last survived summer habitats of the Bakhtiari nomads. The district has harsh winters with heavy snowfall. This makes it an area which is not easy to live in year-round. Because of these geographic/climatic conditions, the area favoured the less sedentary populations until a few decades ago; even today the population decreases sharply during Autumn and Winter, when all Bakhtiari nomads make their temporary camps in lowland Khuzistan, a few hundred kilometres to the west. The first season of the archaeological survey of the Kuhrang district was conducted in September and October 2007, and brought to light 176 sites ranging in date from the Middle Palaeolithic to the Qajar Period (eighteenth/nineteenth century AD) (Roustaei 2007).

Although several Palaeolithic sites were identified in the area during the first season, it was not then recognised that we were dealing with a very special area featuring the high altitude adaptation of hunter-gatherer groups during the Pleistocene. In the second season (2009) our survey focused on the eastern foothills of the Zard Kuh mountain range (Figure 3). The area has a northwest-southeast extension, along the general trend of the Zagros Mountains, and consists essentially of the eroded slopes of an old river valley (Figure 4). The altitude of the surveyed localities ranges from 2450m to 2800m asl. This landscape is exclusively exploited today by the Bakhtiari nomads during the summer. Altogether we identified more than 160 localities of lithic scatters. All localities are open sites and differ in size from a few hundred square metres to more than 35ha. The overwhelming majority are Middle Palaeolithic, although there are some Epipalaeolithic/Early Neolithic sites too. Amongst the Middle Palaeolithic localities, there are at least five huge industrial areas with thousands of surface artefacts. These workshops are formed on several conglomerate outcrops with good amounts of chert/flint nodules as large as 0.4 × 0.4 × 0.4m. In our collected assemblages there are numerous characteristic Middle Palaeolithic artefacts such as Levallois flakes, convergent scrapers, single side scrapers and points (Figures 5–9).
Considering that the survey area during the second season involved just a tiny percent of the foothills of the Zard Kuh mountain range, there are potentially hundreds of localities of probably the same age remaining to be identified. The importance of the discovered Middle Palaeolithic sites in Kuhrang district, needless to say, lies in the fact that no such sites have been discovered in such high altitudes in the Iranian Plateau, and probably in the entire Near East. Although many problems still remain to be answered on their more exact dating, the existence of these sites challenges prevailing hypotheses on human adaptations in high altitude territories during the Pleistocene (see also Roustaei & Biglari in prep).
I would like to express my thanks to Mr Esfandiar Heidari Poor, then the director of the Cultural Heritage Office of Chahar Mahal va Bakhtiari Province, and Miss Mojgan Riahi, then deputy of the same office and now its director, for their continuous encouragement and support. My friend and colleague, Fereidoun Biglari, director of the Palaeolithic Research Department of the National Museum of Iran, accompanied us for a few days in the field and briefly examined all collected lithic samples; I deeply appreciate his help. I would also like to thank the team members, Majid Kouhi Gilavan, Ali Imani, Shahram Abdolvand, Abbas Mohammadi, Zabihollah Masudinia and Mehdi Heidari, for their meticulous work in the field. Finally, my deep gratitude goes to kind and hospitable Bakhtiari nomads, who welcomed us warmly.