Al-Hussein Mosque

The Al-Hussain Mosque (Arabic: مسجد الإمام الحسين‎‎; Egyptian Arabic: جامع سيدنا الحسين) is a mosque built in 1154. (Alternative transliterations include Husayn, Hussain, Husayn, and Hussayn; also, the mosque's name is prefixed by the honorific title Sayyidna). The mosque is located in Cairo, Egypt, near the Khan El-Khalili bazaar. It is considered to be one of the holiest Islamic sites in Egypt.

The mosque was built on the cemetery of the Fatimid caliphs, though this was not known until the site's archaeological excavation. It is named for Muhammad's grandson, Hussain ibn Ali. Dawoodi Bohra and other Sunni Muslims believe that Husayn's head is buried on the grounds of the mosque. The complex includes a mausoleum, which dates back to the mosque's original construction in 1154.

The currently standing building was constructed in the 19th century, and was influenced by Gothic Revival architecture. Today, the mosque houses some items considered sacred by Muslims, such as the oldest complete manuscript of the Quran.

According to Fatimid beliefs, in the year 985, the 15th Fatimid Caliph, Abu Mansoor Nizar al-Aziz Billah, traced the site of his great-grandfather's head through the office of a contemporary in Baghdad. It remained buried in the town of Ashkelon at "Baab al Faradis" for about 250 years, until 1153.

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