Is it true that the shrine of the head of the Prophet Yahya (peace be upon him) is located in the Umayyad Mosque in Damascus, and how can that be when the Messenger (peace and blessings of Allah be upon him) forbade building over the graves of prophets? And if this shrine is imaginary, as Ibn Taymiyyah mentioned, is prayer valid in the Umayyad Mosque?

The presence of the head of Prophet Yahya (John) -peace be upon him- in the Umayyad Mosque is not authentic, because among the graves of the Prophets, only the grave of Prophet Muhammad -peace and blessings be upon him- is known. Furthermore, building over graves was not known or permitted at that time. What is known as the maqam (station/shrine) is merely an empty station that does not contain a real grave, and the verified grave of Prophet Yahya -peace be upon him- is in Palestine, in Jerusalem.