the sultan ahmet mosque, commonly called the blue mosque, is a mosque in istanbul, turkey. it was built between 1609 and 1616, when ahmet i ruled the ottoman empire. like with many other mosques, the founder of the mosque is buried in it. his architect, sedefkar mehmet agha, decorated it like a jeweler would. there is also a madrasah and a hospice associated with the mosque. today it is one of the greatest tourist attractions in istanbul.