The Sanctuary of Imām 'Alī (Arabic: حَرَم ٱلْإِمَام عَلِيّ, romanized: Ḥaram al-ʾImām ʿAlī), also known as the Mosque of 'Alī (Arabic: مَسْجِد عَلِيّ, romanized: Masjid ʿAlī), located in Najaf, Iraq, is a mausoleum which Shia and Sunni Muslims believe contains the tomb of 'Alī ibn Abī Tālib, a cousin, son-in-law and companion of the Islamic Prophet Muhammad.

Baha' al-din al-'Amili was appointed as the architect and the structure was designed in the classical Safavid Persian style.

The Abbasid caliph al-Mutawakkil flooded the site in 850, but in the 10th century Abu'l-Hayja, the Hamdanid ruler of Mosul and Aleppo, rebuilt the shrine in 923, which included a large dome.

In 979–980, the Shi'ite Buyid emir 'Adud al-Dawla expanded the shrine, which included a cenotaph over the burial site and a new dome.

In 1742, Nader Shah gilded the dome and minaret,[6] and this was chronicled by Nasrallah al-Haeri in his famous poem, iḏhā ḍhāmak al-dahra yawman wa jārā (Arabic: إذا ضامك الدهر يوماً وجارا).

In the three years after the 2003 invasion of Iraq by the U.S. military, a number of violent incidents occurred at the mosque: Numerous structures have existed over the tomb of Imam Ali since its discovery during the rule of Harun al Rashid in the 8th century.

[11] The inside of the tomb chamber and its surrounding halls are ornamented with an array of mirror mosaics, most of which has been replaced over the years and are not original.

The gilding of the shrines dome and façade elements occurred in 1743 under the orders of the Iranian king Nader Shah Afshar and his wife Razia Begum.

The courtyard arcades are two floors in height and contain various small chambers historically used as dormitory rooms for seminary students, today most are used as administrative offices.

The original Al-Ras mosque is said to have dated from the Ilhanate period in 14th century however it was demolished in 2005 by the shrine's administration and rebuilt in a modern style using contemporary construction materials and methods.

[11] The original Ilkhanate era mihrab of the Al-Ras mosque underwent restoration in 2023 after having been kept in storage for 18 years and will be put on display in the shrine's museum.

[15][16][17][18][19][20] The Boston Globe reports "for the Muslim Shias, Najaf is the fourth holiest city, behind Mecca and Medina in Saudi Arabia and Al-Aqsa Mosque in Palestine.

[21] A hadith attributed to Ja'far as-Sādiq, the Sixth Imami Shī'ite Imām, mentions the site as one of "five definitive holy places that we respect very much".

I swear to God that no one more honourable than the Commander of the Believers [Ali] has ever lived there after (the time of) his purified fathers, Ādam and Nuh.