ent would, of course, have created havoc with the entire Austrian
forces in the Trentino, but, as stated, the defensive possibilities of
the situation are so formidable that success would appear almost
beyond the realms of actuality.

On the Isonzo front the fighting all along continued on a large scale.
An idea of the immensity of the struggle is suggested by the Austrian
estimate in January, 1916, that Italian casualties had passed the
million mark. Exaggerated as this number was regarded in allied
circles, it showed Austria-Hungary's opinion of the severity of the
fighting in what was considered a subsidiary theatre of the Great War.

The railroad situation on the Isonzo front is, as in practically all
modern military situations, of primary strategic importance. The
Istrian Peninsula is served by three lines, each of which runs to
Austrian bases of supply. One runs up the valley of the Isonzo,
through Gorizia and Tolmino and through the Hochein Tunnel to Vienna.
At Gorizia a branch leaves this line, running southeast, and connects
Gorizia with Trieste across the Carso Plateau. The second line comes
from the east from Laibach through San Pietro, where a branch runs
south to Fiume, and the third comes north from the Austrian naval base
at Pola. Gorizia is served by the northern road from Vienna, from
Trieste by the main line, and by the branch just described. Supplies
from Vienna would be stopped by cutting the road anywhere north of
Gorizia. But to shut off Trieste as a source, both of the southern
rail communications must be cut. Early in June, 1915, the Italians
forced a passage of the Isonzo at Plava and at Monfalcone, and cut the
railroad at these two points. Gorizia then continued to be supplied
only by the Trieste branch. Nor was Trieste itself cut off, as the
road from Laibach through San Pietro continued open. The only way to
isolate Istria was to take the San Pietro junction, and this was the
ultimate aim of the operations at that region.

The Italian objective in Istria was, of course, Trieste. In order to
advance on Trieste the Italians must be secured from a flank attack,
and Gorizia, which is a strongly fortified bridgehead, would be
directly on their flank. Therefore, it must be either captured or
masked before an advance to the south could be started. Gorizia, too,
was important for another reason. It was the point which the
Austrians had chosen to be the center of their first main line of
defense. I