People talk a great deal and have different opinions about the place of the grave of AlHusayn. Can the Muslims benefit from knowing exactly where it is?
Answer: People have in fact differed concerning this. It is said that he is buried in AlSham (The Levant), or in Iraq, Allah knows best what is true. With regard to his head, they also differed concerning that; it was said that it is buried in AlSham or in Iraq or in Egypt. The correct view is that the site in Egypt is not his grave, rather that is a mistake and the head of AlHusayn is not there. A number of scholars have written essays on that and explained that there is no evidence for the head of alHusayn being in Egypt. The most likely view to be correct is the view that it is in AlSham, because it was taken to Yazid ibn Mu`awiyah who was in AlSham. There is no basis for the view that it was taken to Egypt. Either it was kept in AlSham or it was returned to his body in Iraq.
Nevertheless, people do not need to know where he was buried or where his head. Rather what is prescribed is to pray that Allah may forgive him and be pleased with him, for he was killed unjustly. So we should pray for him to have forgiveness and mercy and hope for much good for him. He and his brother AlHasan will be the master youth of Paradise, as the Prophet (peace be upon him) said. May Allah be pleased with them. If a person's grave is known, there is nothing wrong with saying Salam (Islamic greeting of peace) to him and making Du`a' (supplication) for him, as other graves may be visited,
without going to extremes in that or worshipping them. It is not permissible to ask the dead to intercede, because nothing can be asked of the dead. Rather, we should make Du`a' for them and ask Allah to show mercy for them, if they were Muslims, because the Prophet (peace be upon him) said: Visit the graves for they remind you of the Hereafter.
If a person visits the graves of AlHusayn or AlHasan or any other Muslim to make Du`a' for them and pray for them to have mercy and forgiveness, as he would do at the grave of any other Muslim, this is Sunnah (a commendable act). Visiting graves to supplicate to dead people or beseech their help or intercession is a reprehensible action and indeed it is major Shirk (associating others with Allah in His Divinity or worship). It is not permissible to build mosques or domes over graves, because the Messenger (peace be upon him) said: "May Allah curse the Jews and Christians, for they took the graves of their Prophets as places of worship." (Agreed upon by Imams Al Bukhari and Muslim) It is authentically narrated from Jabir ibn `Abdullah (may Allah be pleased with them) that the Prophet (peace be upon him) forbade plastering of graves, sitting on them, and building over them. So it is not permissible to plaster over graves, perfume them, place screens around them or build over them; all of that is forbidden and these are means that lead to Shirk. And we should not pray at the graves, because the Prophet (peace be upon him) said: Beware of those who preceded you and used to take the graves of their prophets and righteous men as places of worship, but you should not take graves as Masjids (mosques); I forbid you to do that. [Related by Muslim in his Sahih (authentic) Book on the authority of Jundub ibn `Abdullaah AlBajaly(may Allah be pleased with him)] This Hadith indicates that it is not permissible to pray at the graves or to take them as Masjids, because this is a means to Shirk and worshipping someone other than Allah by calling upon them (the occupants of the graves), seeking their help, making vows to them, and touching their graves to seek their blessings. Hence the Prophet (peace be upon him) warned against that. Rather graves should be visited in the manner prescribed in Shari`ah (Islamic law) only, to give Salam to them and make Du`a' for them and pray for them to have mercy without traveling specifically for that purpose. Allah is the Source of strength and the Guide to the straight path.