The site is situated near the upper end of the wadi. Its name means “sweet valley”, due to its fertility and. the rich supply of fresh water in its underground. At the northern periphery of the archaeological site small occurrences of copper ore were found. Some of them display traces of ancient surface mining. Indications for copper smelting at the site begin during the transition from the Neolithic to the Bronze Age. At present, this is the earliest proof for metallurgy in SE Arabia. Continued occupation of the site during the Bronze and Iron Ages are evident in the form of typical pottery from these periods. Direct and indirect evidence for metal Production was found in the form of smelting furnaces, workshops, and traces of ore processing. An ingot of pure copper with a weight of 4.6 kg-which, according to the analysed lead isotopes, was produced from local ore-is direct evidence for on-site metallurgy. Isotope analyses of artefacts from other Bronze Age sites indicate that HLO1 is a potential source of copper for a larger area of SE Arabia.