The following day, April 23, 1916, Austrian artillery of all calibers violently shelled the trenches occupied east of Selz, obliging the Italians to evacuate a small section north of the Selz Valley, which was especially exposed to the Austrian fire. Another strong attack, supported by a very destructive gunfire was launched by the Austrians against these trenches on April 25, 1916, and enabled them to reoccupy some of the ground previously lost.
Two days later the Italians attempted to regain these positions. At first they succeeded in entering the Austrian trenches on a larger front than they had held originally, but when they manifested an intention to continue the attack, the Austro-Hungarians, by counterattacks drove them into their former positions and even ejected them from these in bitter hand-to-hand fighting, thereby regaining all their former positions.
During the balance of April, and up to May 15, 1916, military operations on the entire Isonzo front were restricted to artillery bombardments, which, however, at various times, became extremely violent, especially so with respect to Goritz and the surrounding positions.
In the next sector, the Doberdo Plateau, much the same condition was prevalent. From the 1st of April, until the middle of May, 1916, there was always more or less artillery activity. Occasionally infantry engagements of varying importance and extent would occur. On April 7, 1916, the Italians were driven back from some advanced saps. South of Mrzlivrh, Austro-Hungarian troops conquered Italian positions, taking forty-three prisoners and one machine gun.
Again on the 9th, hand-to-hand fighting, preceded by bomb throwing, was reported on the Mrzlivrh front. Another attack, launched early in the morning of April 13, 1916, by the Austrians, lasted throughout the day, with varying fortune, but finally resulted in a success for the Italians. On April 14, 1916, the Austro-Hungarians captured an Italian position at Mrzlivrh and repulsed several counterattacks. The Italians suffered heavy losses. Artillery vigorously shelled the Italian positions at Flitsch and Hontebra.
Other violent engagements took place on the Doberdo Plateau on April 27, May 9, 10, 12, and 13, without, however, having any influence on the general situation.
In all the other sectors very much the same conditions prevailed. Artillery fire was maintained on both sides almost constantly. Infantry attacks were launched wherever and whenever the slightest opportunity offered itself. Scarcely any of these, however, resulted in any noticeable advantage to either side, especially in view of the fact that whenever one side would register a slight gain, the other side immediately would respond by counterattack and frequently nullify all previous successes. Comparatively unimportant and restricted, though, as most of this fighting was, it was so only because it exerted practically no influence on the general situation. On the other hand, it was carried on with the greatest display of valor and persistence that can be imagined and, because of the very nature of the ground on which it occurred, it forms one of the most spectacular periods of the war on the Austro-Italian front.
Of these many local operations there were only a few which developed to such an extent that they need to be mentioned specifically.
One of these was a series of engagements in the Ledro Valley, southwest of Riva and west of Lake Garda. There the Italians on April 11, 1916, by systematic offensive actions, pushed their occupation of the heights north of Rio Tonale, between Concei Valley and Lake Garda. Efficaciously supported by their artillery, their infantry carried with the bayonet a strong line of intrenchments and redoubts along the southern slopes of Monte Pari Cimadoro and the crags of Monte Sperone. On the following day, however, April 12, 1916, the Austro-Hungarians, by violent surprise attacks, succeeded in rushing a part of the trenches taken by the Italians at Monte Sperone. In the evening, after an intense preparation by artillery, Italian infantry counterattacked, reoccupying the lost positions, after a deadly hand-to-hand struggle and extending their occupation to the slopes of Monte Sperone. This was followed by a still further extension on April 16, 1916.
Much of the fighting involved positions on mountain peaks of great height, creating difficulties for both the attacker and the defender, which at first glance appeared to be almost insurmountable. Of this type of warfare in the high mountains, the special correspondent of the London "Times" gives the following vivid description: