The naval side of the First World War in the Adriatic provides a classic case study in narrow sea warfare. This is the story of the Austro-Hungarian KuK Navy's contribution to the Central Powers' considerable effort in the region. This finely balanced, well-handled navy successfully helped to defend Austria's Adriatic base of power--the Pola-Trieste-Fiume triangle--in the north, to protect the vital sea lane to Cattaro and the south, and to support the army from the sea--all against major odds. Its forces also contributed significantly to the U-boat war.During initial stages of the conflict, the French were the enemy at sea. Later, Italy switched allegiances, joining the Entente against her former allies. Because the KuK Kriegsmarine was no match for the Italians and the French combined, the battle fleet was thereafter kept in being at Pola, holding the Allies in check. Nonetheless, the Adriatic became an Austrian lake. Using aircraft, U-boats, torpedoes, and mines, the KuK worked toward reducing the odds against it. However, the impasse would continue until the armistice, ruling out a Mahanian showdown in the Adriatic. Koburger provides important geostrategic points of comparison and valuable lessons for other conflicts, even today.