evidence: Saudi Arabia's eastern boundary follows the Persian Gulf from Ras 'al Khafji to the peninsula of Qatar, whose border with Saudi Arabia was determined in 1965. The border with Oman on the southeastern coast of the Arabian Peninsula runs through the Empty Quarter (Rub 'al-Khali). The border demarcation was defined by a 1990 agreement that included provisions for shared grazing rights and water rights. The border through 'Al Buraymi Oasis, located near the conjunction of the frontiers of Oman, Abu Dhabi (one of the emirates of the UAE) and Saudi Arabia, has triggered extensive dispute among the three states since the Treaty of Jeddah in 1927. In a 1975 agreement with Saudi Arabia, Abu Dhabi accepted sovereignty over six villages in the 'Al Buraymi Oasis and the sharing of the rich Zararah oil field. In return, Saudi Arabia obtained an outlet to the Persian Gulf through Abu Dhabi.