Situated in the city of Soltaniyeh in the northwestern province of Zanjan which used to be the capital of Mongol Ilkhanid dynasty ancient Persia in the 14th century, the Dome of Soltaniyeh is the Mausoleum of Uljaytu, known as Muhammad Khodabandeh, the Ilkhanid ruler (1304-1316).
Registered by UNESCO as a World Heritage Site, the monument is famous for being the third largest dome in the world after the domes of Florence Cathedral in Italy and Hagia Sophia in Istanbul and the oldest double-shell dome in Iran, paving the way for more Iranian-style cupola buildings, such as the mausoleums of Khoja Ahmed Yasawi in Kazakhstan and the Taj Mahal in India.
Standing in the middle of a rural settlement, surrounded by fertile meadows, the three-storey octagonal structure includes eight elevated porticoes, eight slender minarets, several chambers, and an outstanding dome in a height of 48.5 m and a diameter of 25.5 m without any buttresses, covered in turquoise blue faience with different kinds of tile work, making it an exemplary achievement in the development of Persian Islamic architecture.
The main artistic factors in the monument are the inlayed brickworks, plaster moldings, engravings and tile works, creating a kind of harmony that is truly appreciative.
The interior walls were originally faced with light golden bricks and dark blue faience tiles which it was redecorated with plaster in 1313, using various fine ornaments. The walls comprise spectacular engravings in which a verse from the Holy Quran has been inscribed in the beautiful Tholth and Kufic scripts.
The French archaeologist Andre Godard described the monument as "the skillful, confident work of a great builder, a consummate technician who was at the same time an artist. Here is a dome which stands simply by virtue of a perfectly conceived and constructed profile."
Visiting this magical dome and going upstairs to see the beautiful surrounding scene is a fantastic chance for sightseeing, making it a worthwhile stop on the way from Qazvin to Zanjan which should not be missed.