Fundamentally, the Case Blue was focused to the oil. Preliminary offensives in the Crimea were aimed to protect Rumanian oil facilities from Soviet air attacks and even more important, the objective of the main thrust over the river Don was to put oil-rich region of Caucasus into the German hands. The first goal was easily attained but the second was flawed because the Germans haven't really understood the difference between holding oilfields and the efficient utilization of that important resource. It is quite interesting that OKH never discussed in detail the question how the Caucasus oil would be transported to the Reich. Clearly, the assumption was that the oil would be transported over the Black Sea to Rumanian ports or further through the Dardanelles to the Mediterranean Sea. The problem with the Rumanian route was that the Danube fleet was large just enough for the existing Ploesti facilities. At that time Germans lacked sea routes and protection of tankers to use the Russian oil. Transportation of the oil by land was entirely out of question because the German transportation relied almost entirely on draft animals. Obviously, the problem with the objectives of the Case Blue was that whether the Germans seized the Caucasus oilfields intact or not, they have lacked a viable plan to bring the oil to the Reich. Any ideas how the Germans could have materialized their intentions to extract benefits from the Russian oil and use it for the continuation of their war efforts?