The system of underground tunnels was first revealed in 1968, when, under the archaeological direction of Gideon Forester, Israel’s National Parks Authority was preparing the mountain palace-fortress, excavated in the 1960s by Father Virgilio Corbo, for tourists. The system was surveyed and partially excavated under my direction with the assistance of Shimon Arzi and the Field School in Kfar Etzion during 1973–1975. The work at the tunnels was carried out by local volunteers who stayed at the Field School.