The Eastern Front stretched for 1,400 kilometers, from the Arctic Circle in the North, to Crimea in the South, and flashpoints changed all through the war as the two adversaries probed each other and fought over the same increasingly devastated territory. This heatmap shows the major battles of the four-year conflict, beginning with the German advance in the first year, the consolidation, and the pushback by the Soviets in the final two years of WWII.