The muqarnas-domed structure known as Imam al-Dur (Imam Dur) was a mausoleum situated on the east bank of the Tigris some twenty kilometers north of Samarra in Salah al-Din Governorate. It stood close to the escarpments along the river, west of the limits of the modern-day settlement of al-Dur. An inscription on the exterior of the building stated that it was the turba (tomb) of Abu ‘Abd-Allah Muhammad, son of Musa al-Kazim, the seventh Shi’a imam. Another inscription names the patron as the ‘Uqaylid amir Sharaf al-Dawla Muslim ibn Quraysh (d. 1085/478). Scholars date the original building based on the identity of the patron and several other persons mentioned in the inscriptions to the years immediately following the patron’s death in 1085. In the following centuries, patrons added decorations and adjoining components, which fell out of use by the twentieth century. Da’ish (the so-called “Islamic State”) destroyed the building in 2014.
It is a matter of debate whose remains actually lay in the tomb. While the inscriptions name the dedicatee as a son of the seventh Shi’a imam, architectural historians have questioned this dedication and suggested instead that it is the resting place of the patron, Muslim ibn Quraysh. The argument for this interpretation rests on the fact that we are able to date the tomb and its inscriptions to the eleventh or twelfth century on architectural and paleographic grounds, long after the death of the imam and his sons; that the named patron died at the end of the eleventh century; and that the first administrators of the tomb named in the inscriptions were associated with the Seljuk court, a staunchly Sunni institution.
The site was a walled enclosure comprising the square, muqarnas-domed tomb chamber in its southwest corner, a small mosque to the east of the tomb chamber, and a courtyard to the north with the remnants of a portico wrapping around its north, west, and south sides. Access to the complex was through a gateway on its north side, where visitors would enter onto the north portico of the courtyard. Access to the tomb chamber and adjacent mosque were from the south portico of the courtyard. The tomb chamber was the only structure left standing in the early twentieth century when travelers and archaeologists first photographed the ruins. Only the bases of the walls of the courtyard and mosque remained, and these have received little attention.
The dome chamber’s base was a tall, tapering cube bolstered by four corner bastions made of baked brick. Hazarbaf brickwork adorned the corner bastions and a band at the top of the base. Surmounting the cube was a muqarnas dome resting on a tall octagonal drum. The shell of the dome consisted of three increasingly narrower octagonal drums, each rotated slightly to form a spiral effect. At the top of these was a dome-shaped cupola.
One entered the tomb chamber through a door on its north side. The inner chamber was square in plan. Its walls featured stucco ornamentation, including rows of blind lobed arches. These may well date from a later period. Above the cornice, the octagonal drum and rotated octagons forming the four courses of muqarnas were accentuated with scalloped niches. The cupola concluding the dome is decorated on the interior with fluting.
The three inscriptions found in situ deserve further discussion, as the original date of the monument depends on their interpretation. In addition to the dedicatee and the patron mentioned above, the inscriptions also name an Abu Shakir ibn Abi al-Faraj ibn Nasuh as the architect (al-banna’) of the monument. His name appears in both an inscription on the exterior thought to be original and a longer, possibly later inscription on the interior. The longer interior inscription mentions a number of other individuals who served in the upkeep and care of the building. The first of these are the Qadi Mu’nis ibn Hamdan, who was the building’s legal caretaker (mutawalli), and who was succeeded in this role by a Hasan ibn Rafi’. The inscription further states that the building was among the works that the chamberlain (hajib) Abu Ja’far Muhammad ordered to be completed (amara bi-tammamihi), and that after him came two chiefs of police named Abu al-Fath Tahir and his brother, Abu al-Mahasin ‘Abd al-Jalil, sons of Ali bin Muhammad al-Dihistani. Herzfeld identified the last three names in the inscription as members of the Seljuk court who served in their stated positions (chamberlain and chiefs of police) during the reigns of Malikshah and Barkiyaruq. The two brothers were died in 1094 and 1101, respectively, meaning that the completion of the monument under Abu Ja’far Muhammad must have taken place before that, and notably sometime before the accession of Barkiyaruq to the throne in 1094, when Abu al-Mahasin ‘Abd al-Jalil left his post as chief of police to become vizier in Isfahan.
Imam Dur was an important, if understudied, monument in the history of Islamic architecture. Its inscriptions are unusually rich for an early building, especially in Iraq where so little survives intact before the eleventh century and early inscriptions are rare. Formally, the mausoleum is the earliest datable example of the muqarnas dome, a form that appears on numerous buildings in Iraq and the historically connected regions of Khuzistan, the Jazira, and Syria during the twelfth through fourteenth centuries. While its inscriptions and decoration have been closely examined, the history of the changing associations and functions of this monument, which was added to and cared for by both Shii and Sunni patrons, remains to be told.
The tomb was reported destroyed in October 2014.
 For transcriptions of the Arabic text and drawings of the inscriptions, see Max van Berchem, “Arabische Inschriften” in Sarre and Herzfeld, Archäologische Reise, 1: 30-4, and Ernst Herzfeld, Geschichte der Stadt Samarra (Hamburg, 1949), pp. 281-2. The most thorough discussion of the inscriptions, including romanizations of each, is in Leisten, Architektur für Tote, 160.
 Herzfeld, "Damascus," 19-20 and Leisten, Architektur für Tote, 161.
 Leisten, Architektur für Tote, 160
 Leisten, Architektur für Tote, 160-1.
 For an Arabic transcription and English translation of this inscription, see Herzfeld, “Damascus,” 19.