The Dome of Soltaniyeh in Soltaniyeh city, Zanjan Province, Iran, traditionally so called, is a complex of ruins centering on the Mausoleum of the Mongol ruler Il-khan Öljeitü, also known as Muhammad Khodabandeh. The main building, erected between 1302 and 1312 AD, may have the oldest double-shell dome in Iran, a view of the construction made by Dieulafoy, but this has been disputed by André Godard.

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