The Resava originates from the Homolje region in eastern Serbia. It springs out at an altitude of 1,100 m and flows westward between the mountains of Beljanica (on the north) and Kučaj (on the south). In its upper course, the Resava runs parallel to its left tributary, the Kločanica, and area around the villages of Strmosten, Vodna and Stenjevac is known for many caves (Resava Cave, Sokolica, Crystal, etc.).