The Great Mosque of Samarra is a 9th century mosque located in Samarra, Iraq. The mosque was commissioned in 848 and completed in 851 by the Abbasid caliph Al-Mutawakkil who reigned (in Samarra) from 847 until 861. Was at one time the largest mosque in the world; its minaret, the Malwiya Tower, is a vast spiralling cone 52 meters high and 33 meters wide with a spiral ramp. The art and architecture of the mosque was influential; stucco carvings within the mosque in floral and geometric designs represent early Islamic decoration.
The city is also home to the al-Askari Mosque, containing the mausoleums of the 'Ali al-Hadi and Hasan al-Askari, the tenth and eleventh Shia Imams, respectively, as well as the shrine of Muhammad al-Mahdi, known as the "Hidden Imam", who is the twelfth and final Imam of the Shia of the Ja'farī Madhhab. This has made it an important pilgrimage centre for Ja'farī Shia Muslims. In addition, Hakimah Khatun and Narjis Khatun, female relatives of the Prophet Mohammed and the Shia Imams, held in high esteem by Shia and Sunni Muslims, are buried there, making this mosque one of the most significant sites of worship for Shia and a venerated location for Sunni Muslims.