Researching the Nabataean culture was difficult, not least because major sites lay outside his reach due to the Arab–Israeli conflict, such as Petra in Jordan, Hegra (Mada'in Salih) in Saudi Arabia, and Seeia in Syria (Sî' near Kanatha in Jebel Druze).[3] His excavations in the Negev desert included the Nabataean caravan stops of Oboda (Avdat, 1958–61 and 1975–77), Mampsis (1965–67), and Elusa (1973 and 1979–80).[3] This work allowed Avraham Negev to gain in-depth knowledge of the Nabataean civilisation and particularly of its trade network in the Negev region.[3]