USSR unleashed an assault against Finnish army at Äyräpää. Red army lost 15000 men trying to break the defenders

The Battle of Vuosalmi (also known as the Battle of Äyräpää-Vuosalmi) – the main bulk of it – lasted from July 4 to July 17, 1944. It was fought during the Continuation War (1941–1944), a part of World War II, between Finland and the Soviet Union.

After the Soviets saw that they had failed in the Battle of Tali-Ihantala against the Finnish defenders in the late June and early July 1944, they tried to break the Finnish positions in Vuosalmi (now Druzhnoye) and encircle the southern part of the Finnish forces in the Karelian Isthmus. Soviet forces of the 23rd Army in the region had made unsuccessful low-scale attacks against the Finnish defenses for nearly two weeks at Äyräpää region. Lack of success from the 23rd Army's performance lead to change of command on July 3.

Finnish defenses on the Vuosalmi consisted initially with only the 2nd Division (Martola, later Blick). But this was later reinforced with the Armored Division (Lagus) after the battles in the Tali-Ihantala region started to slow down.

Soviet Leningrad Front's 23rd Army (Svetsov) was assigned with the task of making a crossing and a breakthrough at Vuosalmi. For this task 23rd Army assigned first the 98th Rifle Corps and later switched it to the 115th Rifle Corps.

The Finnish positions were very unfavorably located in the ridge of Äyräpää, with the wide River Vuoksi behind. Though the position was very unfavorable, the Äyräpää ridge dominated the lower lands on the northern shore requiring the defensive lines to be placed on the ridge. The Red Army 98th Corps started heavier attacks on July 4 and heavy battles raged for control of the ridge until July 9 when Finns finally withdrew to the northern shore. The Soviet 115th Corps then continued the attack and crossed the Vuosalmi on July 9.

The Soviet 115th Corps reinforced the bridgehead and had all its three divisions in the bridgehead on July 11. The Finns also received reinforcements in the form of the depleted Finnish Armored Division directly from Ihantala and on July 11 both sides were attempting to attack simultaneously. Attempts on both sides were halted when they ran into attacking enemy formations. Though the Soviets now had access to the fields on the northern side, which were advantageous to the Soviet armor, the Finns were able to stop all further Soviet advances. The following Finnish counterattacks in Vuosalmi at this point amounted to not much success either, and thus both sides were on defensive here in mid-July, 1944.

The Finnish artillery fired altogether over 122,000 rounds of ordnance in Äyräpää and Vuosalmi, from June 20 to July 17, 1944 – the same amount as in the Battle of Tali-Ihantala, which was fought during exactly the same time period in a nearby vicinity, on the relatively narrow Karelian Isthmus of Finland.

30,000 men
35 assault guns
200 artillery pieces

60,000 men
150 tanks
300 artillery pieces

Casualties and losses

795 killed
4,976 wounded
354 missing
2 assault guns

3,050 killed
11,750 wounded
250 missing
60 tanks