Cotonou. The bustling port city of Cotonou in the West African nation of Benin offers travelers to a 49-acre (20-hectare) market, fascinating art galleries, and unforgettable architecture. It is the gateway to the world’s only town on stilts and the birthplace of the sacred religion of Vodun. Dantokpa, the largest open-air market in West Africa, covering over 49 acres (20 hectares).