Abstract: The object of this research is the military actions on the Caucasus-Asia Minor Theatre of the Russo-Turkish War in 1877. The subject is the participation of the steamship “Grand Duke Konstantin” under the command of Stepan Osipovich Makarov in the liberation of Abkhazia from Turkish occupation and aid to the Sochi detachment of Shelkovnikov Boris Martynovich in forced crossing the Gagra Gorge. The goal of this research lies in comprehensive examination of the actions of Makarov and his team during cruising at the east coast of the Black Sea, as well as in determination the role and importance of their participation in the military actions in the beginning of August 1877. The conclusion is made that successful actions of Makarov helped the Sochi detachment to avoid heavy losses in Gagra; and that damages inflicted on the Turkish warship “Asar-i Tevfik” during Makarov’s night attack suspended it from evacuation of the Turks from Sukhumi. The reconstruction of the results of torpedo attack and comparison of the tactical and technical characteristics of ships draw particular interest. The author concludes that the Turkish warship that attacked by Makarov at Gagra, was not “Asar-i Şevket”, as described in the pre-revolutionary, Soviet and modern Russian historiography.