and Topčiderka which flows to the north, into the urban center of Belgrade. Human history In Roman period, Kosmaj was an important mining center, but today the mining activities ceased completely. Evidence suggests that the iron ore was extracted even in the pre-Roman period. In Medieval Serbia mining began in c.1420, after the Law on mines was issued by the Despot Stefan Lazarević in 1412. In July 2000, during the excavations for the new sports complex in Babe, a spring was discovered in the valley of the Pruten creek. The new Pruten spring has a capacity up to and by 2011 a waterwork was constructed which supplies the villages of Babe, Stojnik and Ropočevo, so as the complex itself, with the water from this spring. Moreover, during the excavation, a hidden entry into the vast complex of Roman mines was discovered, too, being obscured for centuries. There are evidence of the extraction of silver, iron and lead. In the 3rd century AD, the Kosmaj mines were one of the most important in the Roman Empire, and were administered by the Roman procurator Babenius, whose name is preserved in the name of the Babe village. In the 1970s and 1980s, experts from the National Museum in Belgrade explored the area and discovered many mining necropolis, centered around the villages of Babe, Stojnik and Guberevac. It is estimated that there are some 100 ancient mining shafts on Kosmaj, which go below the ground and are wide. After the Roman period, mining activities ceased, only being revived in the Medieval Serbia. In February 2022, it was announced that the Serbia Zijin Bor Copper company has been surveying the mountain for possible mining. Due to the bad image of the company regarding pollution, this caused public furor, especially due to the ongoing ecological protests. Zijin immediately backed off, saying they are stopping the surveys and that they inherited the 2012 survey rights and partial permits due to the purchase and ownership changes in some other companies. The government confirmed that on Zijin's official request, it issued a survey ceasing decision. The explored area was the Babe-Ljuta Strana survey field, spreading in three municipalities (Barajevo, Sopot and Voždovac), and surveyed ores included lead, zinc, copper, silver and gold. Settlements Except Mladenovac (23,609 inhabitants by the 2011 census of population) on the south-eastern slopes, other settlements, though numerous, are smaller, barely exceeding 2,500 inhabitants. They include