Those “Polish leaders” are remembered in the unknown collective of “The Heroes of the Warsaw Uprising Monument” in a square just outside the Old Town. On the corner of this square is the Field Cathedral of the Polish Army with the “Katyn Chapel -Mausoleum,” to the right of the altar, which “commemorates the martyrdom of 21,857 Polish citizens -war prisoners and captives” in 1940 by “the order of the highest authorities of the Soviet Union” in the Katyn forest in Russia.