 Here, in the fastness of the citadel, lived the emirs, their chief viziers, military leaders, and numerous servants.When the soldiers of Genghis Khan took Bukhara, the inhabitants of the city found refuge in the Ark, but the conquerors smashed the defenders and ransacked the fortress.In the Middle Ages the fortress was worked on by Rudaki, Ferdowsi, Avicenna, Farabi, and later Omar Khayyám.