Mazār-e Sharīf, or just Mazar, is the fourth-largest city of Afghanistan. The name Mazar-i-Sharif means “Tomb of the Prince”, a reference to the large, blue-tiled sanctuary and mosque in the center of the city known as the Shrine of Ali or the Blue Mosque. The region around Mazar-i-Sharif has been historically part of Greater Khorasan and was controlled by the Tahirids followed by the Saffarids, Samanids, Ghaznavids, Ghurids, Ilkhanates, Timurids, and Khanate of Bukhara until the mid-18th century when it became part of the Durrani Empire after a friendship treaty was signed between emirs Murad Beg and Ahmad Shah Durrani.