Istanbul University (Turkish: Istanbul Universitesi) is Turkey s oldest and most prestigious university. Its graduates have been the main source of academic staff for the Turkish university system, as well as providing bureaucrats, professionals, and business people. The campus and faculties are spread throughout Istanbul, the main campus being next to Beyazyt Square.It was founded as an institution of higher education named the Darulfunun (House of Multiple Sciences) on 23 July 1846; but the Medrese (School of theological and environmental sciences), which was founded immediately after Mehmed II conquered Constantinople (Istanbul) in 1453, is regarded as the precursor to the Darulfunun which evolved into Istanbul University. The university celebrated its 550th anniversary in 2003.German historian Richard Honig believes that the history of the Medrese which first evolved into the Darulfunun and later became Istanbul University actually started on 1 March 1321, during the reign of Osman I in Bithynia, the cradle of the Ottoman State.The first modern Applied Physics courses were given at the Darulfunun on 31 December 1863, which marked the beginning of a new period, and on 20 February 1870, the school was renamed as the Darulfunun-u Osmani (Ottoman House of Multiple Sciences) and reorganized to meet the needs of modern sciences and technologies. Starting from 1874, some classes of Literature, Law and Applied Sciences were given at the building of Galatasaray Lisesi, which continued regularly until 1881. On 1 September 1900, the school was renamed and reorganized as the Darülfünun-u Sahane (Imperial House of Multiple Sciences) with courses on Mathematics, Literature and Theology. On 20 April 1912, the school was renamed as the Istanbul Darulfununu (Istanbul House of Multiple Sciences) while the number of courses were increased and the curricula were modernized with the establishment of the Schools of Medicine, Law, Applied Sciences (Physics, Chemistry, Mathematics), Literature and Theology.On 21 April 1924, the Republic of Turkey recognized the Istanbul Darulfununu as a state school, and on 7 October 1925, the administrative autonomy of Istanbul Darulfununu was recognized while the Schools (within the old Medrese system) became modern Faculties. On 1 August 1933, Istanbul Darulfununu was reorganized as Istanbul University (Istanbul Universitesi) following the educational reforms of Ataturk. Classes officially began on 1 November 1933, in the first modern university of the Republic of Turkey.The university has seventeen faculties on five campuses, the main campus being on Beyazit Square in Istanbul, which was known as the Forum Tauri in the Roman period. It has a teaching staff of 2,000 professors and associates and 4,000 assistants and younger staff. More than 60,000 undergraduate and 8,000 postgraduate students follow the courses offered by Istanbul University every year. The main campus with it s landmark gate used to be the Ottoman ministry of war. Located on the grounds is the Beyazit Tower, a 85 m (279 ft) tall fire-watch tower. The grounds before that was the location of the Eski Palace (Old Palace). Some Roman and Byzantine ruins are still visible on the grounds.