A previously unknown area of schistosomiasis transmission is reported based on findings from a travelers' clinic in Barcelona. Three species of Schistosoma (S. haematobium, S. mansoni, and S. intercalatum) were diagnosed in a cluster of 43 patients who had been swimming in the Bandiagara and Bankas districts of Mali, where the Dogon people live. Three villages in the Bankas district appear to harbor these three species. The transmission potential of such a focus in this area is outlined. The travelers involved had little or no information on the risks of contracting schistosomiasis in that area. Obtaining a traveler's history, including accurate geographic data, is shown to be a crucial asset for improving epidemiologic research.