Recent work based on archaeological discoveries suggest that the earliest man inhabited Southwest Asia JEDDAH: A study of archaeological sites in the Arabian Peninsula has shown that the Acheulean civilization had one of the longest lasting tool-making traditions in prehistory, according to research published in Scientific Reports magazine. The research, which commenced in 2014, is the first of its kind to employ scientific methods to examine the history of an Acheulean site. It is part of the Green Arabia project implemented by the Saudi Commission for Tourism and National Heritage (SCTH) in partnership with the German Max Planck Society, the University of Oxford, the Saudi Geological Survey, and King Saudi University in Riyadh. The study focused on the re-evaluation of the Saffaqah site and its archaeological layers using modern techniques and was conducted by experts in prehistoric studies and the ancient environment. It also revealed signs confirming that Acheulean groups inhabited the site about 200,000 years ago, which is evidence of the most recent Acheulean territory in Southwest Asia. The results of the study revealed the changes in human behavior in the ancient world and the natural obstacles our ancestors encountered during their immigration from Africa. Moreover, recent work based on archaeological discoveries suggest that the earliest man inhabited Southwest Asia. According to the aforementioned study, the Saffaqah archaeological site is known for its advanced stone tool manufacture, including stone axes and large fragments. The first scientific study of the site took place during the 1980s under the supervision of the Department of Antiquities and Museums at the time, and was conducted by Professor Norman Whalen, of Texas State University, and a number of Saudi and Arab researchers, with the scientific participation of the Department of Archaeology at King Saud University, represented by Dr. Ghanem Wahida. The first research in Saffaqah showed that the stone tools found in the archaeological site are around 200,000 years old. Their age was identified using uranium-thorium dating. The climatic studies of the Arabian Peninsula showed a rainy climate in the central region 190-240,000 years ago and 75-130,000 years ago which, in turn, led to the formation of several networks of rivers, valleys and vegetation. This contributed to improvements in the living conditions of human groups, making Saffaqah the largest Acheulean site in the Arabian Peninsula, located at the confluence of the tributaries of Wadi Al-Batin and Wadi Al-Sahba. The latest research showed that Saffaqah contains seven archaeological layers, some of which contain Acheulean stone tools. One of the layers contains stone tools in their original place unaffected by natural erosion. The study confirmed that the similarity in the quality of stone tools found in Saffaqah and a number of undocumented Acheulean sites in the Arabian Peninsula indicate that these peoples were present during related periods of time, specifically in Wadi Fatimah and Jiba. The comparative study showed a significant similarity between the stone tools manufactured in Saffaqah and those manufactured in Acheulean sites inhabited during a later period in Ethiopia and Eastern Africa, but differing from those found the Acheulean sites in the Levant. The scientific study conducted by the Saudi research team also highlighted the possibility of a connection between the civilizations of the human groups of the Acheulean Era in Saffaqah and the ancient Middle Stone Age groups. Dr. Abdullah bin Mohammed Al-Sharekh, head of the Saudi research team and faculty member of the Department of Archaeology at King Saud University, said Saudi Arabia has hundreds of prehistoric sites that can provide us with valuable information about human groups that inhabited the region and how they adapted to the prevailing climate and benefited from the natural resources available in their environment.