Shrine of Imam Ali al Hadi and Imam Hassan al Askari

The Al-Askari Shrine in Samarra in central Iraq is one of the most important Shia Muslim pilgrimage sites in the world — the burial place of the tenth Shia Imam Ali al-Hadi (died 868 CE) and the eleventh Shia Imam Hassan al-Askari (died 874 CE), who lived under house arrest in the Abbasid imperial capital of Samarra during the period in which the city was the seat of the caliphate. The shrine also incorporates the Sardab — the underground chamber from which, according to Twelver Shia tradition, the twelfth and final Imam Muhammad al-Mahdi entered occultation in 874 CE, and from which he is believed to be awaiting the divinely-appointed time for his return. The shrine's magnificent gold-sheathed dome, completed in its modern form during the Qajar period in 1905, was destroyed in February 2006 in a major bomb attack carried out by Sunni jihadist militants of al-Qaeda in Iraq during the Iraq insurgency, an attack that triggered a wave of sectarian killings across Iraq and contributed significantly to the descent of the country into civil war. The two surviving minarets were destroyed in a follow-up attack in June 2007. Reconstruction of the dome and the minarets — with substantial Iranian financial and technical support — was completed in 2015, and the shrine has since reopened to pilgrims, although the security and political situation in Samarra continues to evolve.