ALG-477. This natural arch is located on Adrar Mountain near the village of Bordj-El-Haoues on the vast Tassili National Park, wilaya (province) of Illizi, Algeria. The opening has a measured span of about 38.0 meters and is actually the largest arch of the whole park. It is situated close to the guelta of In-Thae, a splendid pool of water with an abundance of reeds located below a lava waterfall. 29R 578767 2755819