Ali Sabieh (Cali Sabiix in Somali), the capital of the eponymous region, is the second-largest city in the Republic of Djibouti. The settlement in this area is several centuries old. At first, it was a simple border spot, where nomads used to stop for water, then set up as a stronghold for the defense of the colony, thanks to its strategic location on a wide basin surrounded by granitic mountains near the Damer crossing. During the Middle Ages, the Ifat and Adal sultanate ruled the area. In the 1900s, after the construction of the railway linking Djibouti to Addis Ababa (the first railway in French Somaliland), the city became an administrative and commercial center.