One century after its discovery, the Columns Tomb of Kumbi Saleh (Mauritania) remains an archaeological riddle. Since 1914, six field programs have been successively carried out at the medieval urban site of Kumbi Saleh, which now is commonly identified as Ghana. The latter was the famous capital city of the medieval West African state, which controlled the gold mines of West Africa and was involved in the gold trade with North Africa and the Mediterranean Basin. However, interpretation of the tomb, the largest structure from the necropolis, is still an issue as its dating itself has never been firmly established. As a consequence, scholars have usually referred to an unsatisfactory timeframe spanning 1000 years. The study of this monument was recently resumed, motivated by the rediscovery of bones collected in the tomb in 1914 and stored at the Musée de l'Homme (Paris, France). AMS radiocarbon dating of the bone and tooth apatite fraction of three skulls demonstrates that the three individuals occupying the main vault of the tomb died between the end of the 11th century and the 12th century, precisely at the time of expansion of the Muslim Almoravid movement south of Sahara.