The Đetinja River, as the Matijaševića reka, originates from the southeastern slopes of the Tara mountain, in western Serbia, near the field of Pusto polje. From the source to its mouth, the river flows in the eastern direction. First, it runs through the small Kremna depression, between the Tara and Zlatibor mountains, following the northern border of Mt. Zlatibor. At Kremna, five streams flow into the one river, forming Đetinja: Matijaševića reka, Konjska reka, Bratešina, Užički potok and Tomića potok.