(Behzad / Musee d'Histoire De La Medicine/Archives Charmet/Bridgeman Art Library)]In 1120, a Muslim doctor was on his way to see his patient, the Almoravid ruler of Seville. The hospital was used until the beginning of the 20th century when it was replaced by the modern University Hospital. Ibn Zuhr also wrote about how diet and lifestyle can help a person avoid developing kidney stones. Ibn Zuhr established surgery as an independent field by introducing a training course designed specifically for future surgeons before allowing them to perform operations independently. They established hospitals and the professions of surgery, medicine and pharmacy, invented surgical instruments and applied empirical methods to test hypotheses.