Rocznica Zbrodni Katynskiej
The commemoration of the 1940 Katyn massacre, when the Soviet NKVD executed approximately 22,000 Polish officers, intellectuals, and elite citizens in the Katyn forest. For decades, the Soviet Union blamed the massacre on Nazi Germany, and the Polish communist government enforced this lie. The truth was only acknowledged by Russia in 1990. The day is observed with ceremonies at the Katyn monuments in Warsaw and at the military cemetery in Katyn.