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.
On 18 March 1921, the treaty ending the Polish-Bolshevik war (the so-called Treaty of Riga) was signed in Riga.
