Koca Mi'mâr Sinân Âğâ (Ottoman Turkish: خواجه معمار سنان آغا; Modern Turkish: Mimar Sinan, pronounced [miːˈmaːɾ siˈnan]) (c. 1489/1490 – July 17, 1588 was the chief Ottoman architect (Turkish: "Mimar") and civil engineer for sultans Suleiman the Magnificent, Selim II, and Murad III. He was responsible for the construction of more than three hundred major structures and other more modest projects, such as his Islamic primary schools (sibyan mektebs). His apprentices would later design the Sultan Ahmed Mosque in Istanbul, Stari Most in Mostar and help design the Taj Mahal in the Mughal Empire.
The son of a stonemason, he received a technical education and became a military engineer. He rose rapidly through the ranks to become first an officer and finally a Janissary commander, with the honorific title of ağa. He refined his architectural and engineering skills while on campaign with the Janissaries, becoming expert at constructing fortifications of all kinds, as well as military infrastructure projects, such as roads, bridges and aqueducts. At about the age of fifty, he was appointed as chief royal architect, applying the technical skills he had acquired in the army to the "creation of fine religious buildings" and civic structures of all kinds. He remained in post for almost fifty years.