Soltaniyeh is a city in and capital of Soltaniyeh District of Abhar County, Zanjan Province, Iran. At the 2006 census, its population was 5,684, in 1,649 families. Soltaniyeh, located some 240 kilometres (150 mi) to the north-west of Tehran, used to be the capital of Mongol Ilkhanid rulers of Persia in the 14th century. Its name translates as "the Imperial". In 2005, UNESCO listed Soltaniyeh as one of the World Heritage Sites. The road from Zanjan to Soltaniyeh extends until it reaches to the Katale khor cave.
William Dalrymple notes that Öljaitü intended Soltaniyeh to be "the largest and most magnificent city in the world" but that it "died with him" and is now "a deserted, crumbling spread of ruins."