KHAYBAR OASIS, SAUDI ARABIA—A fortification that surrounded the Khaybar Oasis some 4,000 years ago has been found in the North Arabian Desert by researchers from the French National Center for Scientific Research and Saudi Arabia’s Royal Commission for Al-‘Ula, according to a Cosmos Magazine report. The nine miles of walls, which were between five and eight feet thick, enclosed more than 2,700 acres. Remains of more than 70 bastions set into the walls for the defense of the oasis settlement have been identified. This fortress was one of a network of walled oases in the region. Read the original scholarly article about this research in Journal of Archaeological Science: Reports. To read about 7,000-year-old rectangular complexes found in the northwest deserts of Saudi Arabia, go to "Around the World: Saudi Arabia."