The Dome of Soltaniyeh (; ) – variously called the Mausoleum of Oljaytu, Tomb of Uljaytu, among other designations – is a historic mausoleum and monument complex, located in Soltaniyeh, Zanjan, Iran. It was built as the mausoleum of the Ilkhanid Mongol ruler Öljaitü (also known as Muhammad Khodabandeh). It was originally the centerpiece of a larger complex of buildings that included a mosque, residences, and other services, though these other buildings have generally not been preserved.
The mausoleum was built sometime between 1307 and 1313 CE. Its double-shelled main dome is one of the largest brick domes in the world, measuring almost in diameter and approximately high.
The Mongol presence in Iran was marked by a shift away from traditional cities dependent on an agricultural hinterland to ones with an emphasis on access to pasture. An example of this new type of Mongol city was the city of Sultaniyya in northwestern Iran. Arghun, the Ilkhanid ruler of Iran at the time, established Sultaniyya as his summer capital. His son, Muhammad Oljeitu Khudabanda, furthered the city’s development and transformed it into the capital of the empire. After Oljeitu’s death, the city began a steady decline. Today, only two buildings remain that which show evidence signs of Sultaniyya’s its former wealth and importance: the octagonal tomb of the Dome of Soltaniyeh and an adjacent khanaqah, a building designed specifically for Sufi gatherings as a spiritual retreat. The quality of the preserved tomb attests to the richness of its patronage by the Sultan Oljeitu.
The large domed tomb chamber of Oljeitu was meant to rival the colossal tomb built by the Seljuq Sultan Sanjar at Merv in 1157. The tomb of Oljeitu has an octagonal plan, like the Tomb of Ahmed Sanjar, with both complexes being sponsored by the Ilkhanid court and were considered some of the most prestigious buildings at the time.
The Global Heritage site of Gonbad-e-sultaniyeh has been recognised as a UNESCO World Heritage Site since 2005. It followed the specific historic UNESCO criteria landscape of four characteristics: ancient and historical monuments, farms, urban landscapes, and the Historical Grass of Soltaniyeh.
Architecture and interior design
The Dome of Solteniyeh was one of the largest religious endowments of the 14th century, and was utilized for multiple functions, such as Quran reading, praying, teaching, housing, and medical purposes.
The construction of the double-shelled dome employed an interlocking arched herringbone network. The Dome of Soltaniyeh was one of the first to use this pattern in Iran, and is unique in choosing brick for its material as previous similar architectural structures often utilized wood.
As for the interior of the tomb, it is decorated in tile and plaster. The insides of the iwans’ walls possess white inscriptions that stand out against the blue background. The underside of the iwans are stuccoed with bands of ornament, that were later painted. A significant inscription--outlined with ogival forms sculpted over cloth--circles the entire dome. The galleries have low, wooden or marble railings. The windows are fitted with bronze screens, along with bronze knobs and balls set with gold and silver.
Following Islamic convention, Oljeitu’s tomb was placed in a garden, known in the Quran as a rawda. This word was also added to the railing of the Prophet Muhammad’s tomb in Medina. Because of this, rawda became the label for funerary structures in Iran. Thus, Oljeitu’s tomb was referred to as a rawda. Additionally, Oljeitu ensured that water could be successfully stored and utilized in the complex, through the use of qanats and wells. A qanat is a downward sloping channel intended to transport water. Due to this, the flora and fauna surrounding the tomb were able to survive for a long time; specifically, “the gardens around the tomb complex were still being maintained in the seventeenth century.” According to a later drawing of the tomb by Flandin and Coste, one can see possible evidence of a cap wall projecting from the northeast corner.
Influence on other monuments
Because Oljeitu’s tomb was one of the most significant works of its time, it became an inspiration for many other complexes, both within and outside of Ilkhanid culture. Distinct features of the complex were later found on many other monuments, such as placement of paired minarets above a portal. This trend began in the Seljuq period, then became a normal inclusion in Ilkhanid buildings.
The Tomb of Oljeitu, like other Ilkhanid tombs, was integrated into a great complex--which no longer remains. These complexes were the “precursors of the type of large, planned funerary complexes, known as kulliye, that (were) built by the Ottomans at Bursa and elsewhere beginning in the second half of the fourteenth century.”
Finally both domes, feature a double-shelled structure. The Dome of Soltaniyeh was the first example of this structure in Iran, and several scholars hypothesize that it is possible for the construction system of Soltaniyeh to have been disseminated from Iran to Brunelleschi in Italy, in the time span of almost a century.