Issued in 1955 to commemorate the 10th anniversary of Warsaw’s liberation (1945–1955), this 40 groszy stamp features a dramatic socialist-realist design with a monument sculpture and national flags set against the rebuilt city skyline. The strong brown monochrome engraving captures the resilience and reconstruction spirit of post-war Poland. The dated inscription “1945–21.IV–1955” marks the historic liberation day. A classic mid-century Eastern Bloc commemorative, popular with collectors of history, architecture, and Cold War-era themes. A solid addition to Poland thematic or post-war Europe collections.