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. If it fell, not only was the way open for an advance on Trieste, but the entire Austrian line to the north and south was jeopardized through the fact that, with the center pierced, both wings were exposed to flank attacks, and would have to retreat or be rolled up and defeated in detail. In other words, the fall of Gorizia would uncover Austria's entire Isonzo line, and, although there might be some subsequent resistance in the mountains to the north, the giving way of the line would be inevitable. Gorizia, however, as has been shown, stands in the front rank of strong natural defensive positions. The foothills of the Julian Alps descend sharply to a plain near where the Isonzo issued from the gorge which it has cut through the mountains. The line between the plain and the mountains is sharp and clearly marked. There is no gentle tapering off of one into the other. This line between the hills and plain is somewhat irregular in shape and incloses a pocket in which Gorizia is situated. It is not unlike a huge elliptical stadium. At the north end, level with the ground, is Gorizia, with the Julian Alps mounting on all sides. The southern bank is constituted by the plateau of the Carso, in which is situated the town of Doberdo. Thus the plain of Gorizia is surrounded on three sides by elevations which serve as admirable watchmen for the city beneath. Just across the Isonzo from Gorizia are the town and spur of Podgora, which absolutely command the city and prevent an Italian attack from that side. With Podgora completely in Italian hands, it is difficult to see how Gorizia could hold out. From Podgora the depots, barracks, and supply houses of Gorizia are within artillery range of guns of all calibers, and the environs of Podgora have changed hands several times.