The Trans-Arabian pipeline, which transported Saudi oil from Dhahran in the Persian Gulf to the port of Zaharani in Lebanon, passing along its 1,214 kilometer way through Jordan and Syria, was haunted by the Arab-Israeli conflict throughout its years of operation and even before. Constructed in 1949-50, its owners carefully chose its route so as to circumvent Palestine/Israel. But in the 1967 war, Israel occupied the Golan Heights, where 40 km of the pipeline were laid down, and consequently became a transit state of this American-Saudi oil exporting endeavor together with Syria, Lebanon and Jordan. This paper explores the Tapline project by focusing on its cross-border and cartographic dimensions from surveying its route in 1949-1950 to Tapline’s involvement in the 1960s in Syrian-Israeli disputes over the location of their shared Armistice Line (and also in Syrian-Lebanese disputes over the location of their boundary in close proximity to Israel), and concluding with the 1967 war and Israeli cooperation with this Trans-Arab project, on the one hand, and Palestinian response to this cooperation on the other hand. By focusing on Tapline, the paper demonstrates the gap between the image of Arab-Israeli borders (particularly Syrian-Israeli borders) as sealed and impregnable in theory and their permeability in practice.