This was a Soviet two-part offensive, otherwise known as the 'Mga Offensive Operation' or '3^rd Battle of Lake Ladoga', intended to break the siege of Leningrad (22 July/25 September 1943).

Since the time that German forces of Generalfeldmarschall Wilhelm Ritter von Leeb’s Heeresgruppe 'Nord' had begun their siege of Leningrad on 8 September 1941, Soviet forces had launched several counter-offensives in 1941, 1942 and most recently in the spring of 1943 with the failed 'Krasny Bor' (polar star) operation. The only Soviet success up to this time had been that 'Iskra' ('4^th Sinyavino Offensive Operation') of January 1943, when a land corridor had been opened between Leningrad and the rest of the USSR along the southern shore of Lake Ladoga. This corridor remained within range of German artillery on the Sinyavino heights, however, and the Soviets therefore planned a new offensive, designed to widen this corridor, for July 1943.

The offensive was to be carried out by General Leytenant Filipp N. Starikov’s 8^th Army of General Kirill A. Meretskov’s Volkhov Front and General Major (from 29 August General Leytenant) Mikhail P. Dukhanov’s 67^th Army of General Polkovnik Leonid A. Govorov’s Leningrad Front against elements of Generaloberst Georg Lindemann’s 18^th Army of what was now Generalfeldmarschall Georg von Küchler’s Heeresgruppe 'Nord'. The planned operation’s objectives were to defeat of the German forces in the area of Mga on the Mga river to the south-west of the Sinyavino heights, to restore Soviet control over the Kirov railway and to ensure a reliable connection by rail between Leningrad and the rest of the USSR.

The Soviet forces were deployed with the 8^th Army on the shorter eastern length of the front line between Gaitolovo and Voronovo with the task of advancing to Mga via Mikhailovsky, and the 67^th Army on the longer northern length of the front line between Gaitolovo and the Neva river at Arbusovo with the task of advancing to Mga after securing a bridgehead across the Neva river between Arbusovo and Anenskoye.

The German formation facing the Soviet onslaught was General Gustav Fehn’s (from 19 August General Ernst von Leyser’s XXVI Corps. The formations controlled by the XXVI Corps were, from left to right, Generalmajor Friedrich von Schellwitz’s (from August Generalleutnant Horst von Mellenthin’s 23^rd Division, Generalleutnant Siegfried Thomaschki’s 11^th Division and Generalleutnant Conrad-Oskar Heinrichs’s 290^th Division on the Sinyavino heights, Generalleutnant Ernst-Anton von Krosigk’s 1^st Division, Generalleutnant Fritz Lindemann’s (from 2 August Generalleutnant Herbert Wagner’s) 132^nd Division and Generalleutnant Dr Julius Ringel’s 5^th Gebirgsdivision.

After a 90-minute artillery preparation and very heavy air attacks, at 06.35 on 22 July the Soviet formations went onto the offensive. The units of the 8^th Army’s first echelon immediately succeeded in taking the Germans' first line of defence, but the offensive advanced no farther against the 1^st Division, 132^nd Division and 5^th Gebirgsdivision. Late in July, the Soviet command brought into battle the 379^th Division and 165^th Division, which replaced the 18^th Division and 256^th Division, but this failed to change the situation in favour of the Soviets. The divisions that entered the battle suffered heavy losses, as German units put up fierce resistance and constantly counterattacked.

On 12 August, in a renewed attack, the 8^th Army took the strong German bridgehead to the east of the Naziya river near Porechye, but failed to break through toward Mga river despite the introduction of the 311^th Division, which was the 8^th Army’s last available reserve, as the German command was able to implement a swift strengthening of the defence. For several days, Soviet troops sought to make a farther advance, but achieved nothing in the war of significant results.

Much the same course of events eventuated on the western end of the Soviet offensive. On 22 July, at the same time as the 8^th Army’s drive, formations of the 67^th Army went onto the offensive, and partially broke the German defences, but failed to exploit their initial success. The German command strengthened its defences with reserves, in the form of Generalleutnant Curt Siewert’s 58^th Division, Generalleutnant Harry Hoppe’s 126^th Division from Generalfeldmarschall Ernst Busch’s neighbouring 16^th Army) and, toward the end of the operation, Generalleutnant Günther Krappe’s 61^st Division. The Soviet offensive was thus halted.

Even so, fierce fighting lasted several weeks and each side sustained heavy losses. Toward the end of August, the fighting gradually began to subside and effectively halted on 22 August. Despite the severity of the fighting, the Soviet troops failed to reach the targets set before the start of the operation, and the front line in the area of the Sinyavino heights had changed only very slightly from the front line at the beginning of the Soviet effort, which is sometimes known as the '1^st Mga Offensive Operation'.

On the orders of the Stavka, Govorov and Meretskov prepared a new offensive only a few weeks after the failure of their first operation. This time the goals of what became known as the '2^nd Mga Offensive Operation' were much more closely defined, and now comprised only the seizure of the Sinyavino heights.

The Leningrad Front had meanwhile rested and revitalised General Major Nikolai P. Simoniak’s XXX Guards Corps in the Leningrad area for redeployment to the area lying to the south of Schlüsselburg (Petrokrepost in Russian) on a temporary subordination to Dukhanov’s 67^th Army. The plan was now to employ this formation in an attack on the Sinyavino heights, which were already opposed by the 11^th Division and 268^th Division, directly from the north. To its left. the XXX Guards Corps was to be supported by the 43^rd Division and 123^rd Division, and to its right by the 120^th Division, 124^th Division and 196^th Division. At the same time, Starikov’s 8^th Army of the Volkhov Front was to support the northern offensive with a westward attack between Voronovo and Gaitolovo.

The renewed offensive got under way during the morning of 15 September. On this occasion, the Soviets made use of a new artillery concept, in which the artillery did not pause its fire as the Soviet infantry moved forward. The attack of the XXX Guards Corps' three divisions was somewhat more successful than that of a few weeks earlier. The defenders of 11^th Division and 290^th Division on the Sinyavino heights were totally surprised by the new artillery concept, so the Soviet attack units succeeded in gaining several hundred metres. The 18^th Army responded rapidly, however, by moving Generalleutnant Friedrich Schulz’s 28^th Jägerdivision as well as Generalleutnant Bruno Frankewitz’s 215^th Division and Generalleutnant Günther Krappe’s 61^st Division to the front, and with these reinforcements the Germans quickly contained the Soviet intrusion. In the following days, the 67^th Army continued to press the German formations as it tried to advance into the lower and flatter land to the south of the Sinyavino heights and thus to be in the position to take Mga. These efforts were universally unsuccessful. The 8^th Army’s attack from the east gained scarcely any ground.

On 18 September, therefore, the Stavka ordered an end to offensive operations. On 24 September, the fighting for the heights flared up again briefly before the front stabilised once more.

In the two components of the '4^th Sinyavino Offensive Operation' the Soviets failed to reach their objectives and suffered heavy losses, in the order of 90,000 men. The Germans also lost heavily, in the form of some 30,000 men, who could be replaced only with great difficulty as the Battle of Kursk was raging in 'Zitadelle' over much the same time. However, the next Soviet offensive, fought from January 1944 as the 'Leningrad-Novgorod Strategic Offensive Operation', would break the German resistance round the Sinyavino heights and lift the siege of Leningrad.