The UNESCO-listed Dome of Soltaniyeh is located in the Iranian city of Soltaniyeh.
The monumental mausoleum was built between 1302 and 1312 for Öljaitü, the eighth ruler of the Ilkhanate. Soltaniyeh served as the Ilkhanid capital, and the dome was intended to house the remains of Imam Ali and Imam Husayn, although those relics were not transferred there.
The building’s enormous turquoise double-shell dome rises above an octagonal structure surrounded by minarets. Its construction represents a major stage in the development of Persian and Islamic domed architecture, especially in the use of a double-shell system and a tall, visually dominant profile.
Soltaniyeh is sometimes confused with Tabriz, another important Ilkhanid city, but the mausoleum is in the separate former capital of Soltaniyeh, southwest of Tehran.