Meymoon Dej

Iran, Iran

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Meymoon Dej, also known as Maymun-Diz, was a major fortress of the Nizari Ismailis in northern Iran during the Alamut period.

Built in a highly defensible mountain location near the famous Alamut stronghold, it was regarded as one of the most important castles of the Ismaili state and served as a key center of power. The fortress stood on a steep rocky height and was protected by strong walls, making it extremely difficult to attack.

It is especially known for its role in the Mongol invasion of Iran, when the last Nizari Ismaili ruler, Rukn al-Din Khurshah, surrendered there to the forces of Hulagu Khan in 1256. After the surrender, the fortress was destroyed by the Mongols, marking the collapse of the Nizari Ismaili state in Iran. Although little remains today, Meymoon Dej holds great historical significance as one of the most important strongholds in medieval Iranian history.