In 1866 the Austrian Kraków fortress was under construction. In preparation for the war with Prussia, it was provisionally completed and equipped in the event of a siege. The crew of the fortress (over 14 thousand soldiers) had the task not only to defend it but also to guard the western Galicia railway. To this end, part of the soldiers were sent to fight in the field. The command of the fortress failed to manage these operations properly and, as a result, despite the victory in the battle of Auschwitz (June 27, 1866), the Austrian troops abandoned the defense of their own railway and concentrated near the Krakow fortress. This situation was used by the weaker Prussian troops (about 6.5 thousand soldiers), who occupied without a fight the border region of Galicia, which enabled the Prussian command to transfer the Hungarian volunteer György Klapka legion to this area; the legion was to begin the anti-Austrian diversion in Hungary. As a result of the rapid end of the Austro-Prussian War, the role of the Kraków fortress and its crew in this conflict was of minor importance. It turned out that the fortress provided suffi cient protection for the greater part of Galicia against the Prussian threat, but its fi eld divisions were ineffi ciently used and had no influence on the course of the war.