Rioni River
Upper Paleolithic remains have been investigated in Satsurblia, Devis Khvreli, Sakazhia, Sagvarjile, Dzudzuana, Samertskhle Klde, Gvarjilas Klde and other cave sites. A cave at Dzudzuana has yielded the earliest known dyed flax fibers that date back to 36,000 BP. At that time, the eastern area of the South Caucasus appears to have been sparsely populated in contrast to the valleys of the Rioni River and Kvirila River in western Georgia. The Paleolithic ended some 10,000-12,000 years ago to be succeeded by the Mesolithic culture (Kotias Klde). It was when the geographic medium and landscapes of the Caucasus were finally shaped as we have them today.