A vibrant 5 kobo commemorative stamp issued by Nigeria in 1973 to mark the 10th Anniversary of the Organisation of African Unity (1963–1973). The design features the OAU Headquarters building set against stylized greenery, with bold blue and yellow colour blocks that highlight the modernist architecture. This issue celebrates African unity, cooperation, and the shared vision of the continent’s early post-independence era. A meaningful thematic addition for collectors of African history, political organisations, and Nigerian philately. Excellent for both single-country and pan-African collections.