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The mausoleum of Soltan Mohammad Khodabandeh (A.K.A Oljaytu) was constructed in 1302–12 in the city of Soltaniyeh, the capital of the Ilkhanid dynasty, which was founded by the Mongols. Situated in the province of Zanjan, 310 km northwest of Teheran. The octagonal building is crowned with a 50 m high dome covered in turquoise-blue faience tiles and surrounded by eight slender minarets. It is the earliest existing example of the double-shelled dome in Iran. scholars such as A.U. Pope have described the building as ‘anticipating the Taj Mahal’.