The Maragheh observatory (Persian: رصدخانه مراغه), also spelled Maragha, Maragah, Marageh, and Maraga, was an astronomical observatory established in the mid 13th century under the patronage of the Ilkhanid Hulagu and the directorship of Nasir al-Din al-Tusi, a Persian scientist and astronomer. The observatory is located on the west side of Maragheh, which is situated in today's East Azerbaijan Province of Iran. It was considered one of the most advanced scientific institutions in Eurasia because it was a center for many groundbreaking calculations in mathematics and astronomy.