This Austrian 4 schilling stamp was issued in 1978 to commemorate the Universal Postal Union (UPU) Congress held in Vienna. The design features a map of Europe in green set against a blue sea, symbolizing international postal cooperation. Below the map is the Austrian Parliament building in Vienna, rendered in bold blue and green tones. The inscription "I.P.U. WIEN 1978" refers to the International Postal Union Congress. Designed by O. Zeiller, the stamp reflects Austria’s role as host of this significant philatelic event.