Work of the first 200 km part of the line from Konya to Bulgurlu was allowed to proceed on the July 27, 1903, as per the Convention. The main contractor was again Holzmann & Co. This first section is relatively flat and straight, it was built quickly and ready for opening on the Sultan Birthday, October 25, 1904.
It has been noted at the time that both the Société Impériale Ottomane du Chemin de Fer de Baghdad and Holzmann made very little use of German expatriates. Most of the engineers and workers working on the site were of Italians, Greeks, Armenians or Turkish origin.
Difficulty in fund raising and in engineering slowed again very much the project. Work on the second 900 km part of the line, from Bulgurlu to Nusaybin was given a go ahead on 2nd June 1908. But the 1908 Young Turks revolution delayed the actual start again. The Swiss based contractors started work in December 1909. By then, the Hedjaz railway railway was substantially completed and August Heinrich Meissner, its chief engineer, was transfered to the CIOB to supervise the works.
In the mean time, the Deutsche Bank acquired in 1906 the Mersin Tarsus Adana railway. This railway served as a starting point both westward towards Bulgurlu and eastward toward the Anamus Mountains. A fourth ground breaking area was started in Alep to build the easy part across the desert. Alep was already connected to Rayak since 1906 by the standard gauge track of "Société Ottoman du Chemin de Fer Damas Hama et Prolongements" (DHP).
In 1914, at the outbreak of the war, the second part of line was almost complete except for the main tunnels across the Taurus (Cilician Gates) and the Anamus. The third part from Nusaybin to Baghdad was also started with 125 km from Sammarah to Baghdad opening in October 1914....
....The uncompleted tunnels created big bottlenecks, hampering supplies transportation from Anatolia to the Ottoman and German armies stationed in Mesopotamia. Tunneling works were accelerated and in 1917, the 600mm gauge track that was laid for construction purpose finally came through both tunnels. It was then used across the unfinished tunnels to carry war supplies using a fleet of about one hundred engines that were supplied by Henschel from 1916 to 1918. All these engines were Bt type (0-4-0 tank), except for five E (0-10-0) fireless type. The tunnels were fully completed in 1918, a few days before the Moudros Armistice.
From: http://freepages.military.rootsweb.com/ ... eGreatWar/