The Blue Mosque in Istanbul, also known by its official name, the Sultan Ahmed Mosque, is an Ottoman-era historical imperial mosque located in Istanbul, Turkey. A functioning mosque, it also attracts large numbers of tourist visitors. It was constructed between 1609 and 1616 during the rule of Ahmed I. The Blue Mosque has five main domes, six minarets, and eight secondary domes. The design is the culmination of two centuries of Ottoman mosque development. It incorporates many Byzantine elements of the neighboring Hagia Sophia with traditional Islamic architecture and is considered to be the last great mosque of the classical period. The architect, Sedefkâr Mehmed Ağa, synthesized the ideas of his master Sinan, aiming for overwhelming size, majesty and splendor. The upper area is decorated with approximately 20,000 hand-painted glazed ceramic in 60 different tulip patterns. The lower stories are illuminated by 200 stained glass windows. The mosque is preceded by a forecourt with a large fountain and special area for ablution. An iron chain hangs in the court entrance on the western side. Only the Sultan was allowed to ride into the mosque horseback, and he would need to lower his head to not hit the chain, a symbolic gesture ensuring the humility of the ruler before Allah.
