The Sultan Ahmed Mosque is an historic mosque in Istanbul. The mosque is popularly known as the Blue Mosque for the blue tiles adorning the walls of its interior. It was built from 1609 to 1616, during the rule of Ahmed I. Its Külliye contains a tomb of the founder, a madrasah and a hospice. While still used as a mosque, the Sultan Ahmed Mosque has also become a popular tourist attraction.
The Sultan Ahmed Mosque has one main dome, six minarets, and eight secondary domes. The design is the culmination of two centuries of both Ottoman mosque and Byzantine church development. It incorporates some 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 splendour.