Which marked a turning point in World War 2 on the European front in favor of the Allied forces?

In 1943 the Germans lost an entire field army along with the Battle of Stalingrad in February, were completely ejected from North Africa in May, lost Sicily in six weeks in July and August. American and British troops landed on the mainland of Europe in Italy, and Italy, one of the three major Axis powers, surrendered. Despite enormous loses in the east the Germans still had enough strength left to mount their last true counter-offensive at Kursk, in July, 1943. This was the largest battle of all time, and a complete failure for the Germans. The Soviets themselves went on the offensive after Kursk, and the Germans were never able to stop them until they were in Berlin. The Germans were never again able to collec a sufficient surplus of strength to attack as they had in 1941, 1942 and 1943. (The "Battle of the Bulge" or The Ardennes Offensive, in December, 1944, while a massive attack by three armies was still on a much smaller scale than Kursk, and moreover was a move born of desperation. For instance, for it to succeed, the German plan called for capturing American gasoline to keep their tanks rolling, and the entire success of the plan depended on this happening, which hope was unmet.)