On April 11, 1943, the first news about the crime committed in the forest near Katyn was released to the world.

On 4 July 1943, at 23:07, moments after take-off from Gibraltar Airport, Liberator II aircraft AL523 with General Władysław Sikorski on board, crashed into the Mediterranean Sea.

The Polish-Bolshevik war broke out on 14 February 1919. The site of the first confrontation was the town of Mosty near Szczuczyn in the Grodno region, where Polish Army units halted the Red Army’s march.