Doubtless, the Topkapi Palace is located in the most beautiful point of Istanbul that Sultan Mehmet cut off the point of the Constantinopolitan triangle by building a massive defense-wall, guarded by towers, which extended from the Byzantine sea-walls; this was Topkapi the Canon Gate, so-called because it bristled with armaments.
The Topkapi Palace was built by Sultan Mehmet the Conqueror between 1465-1478. The palace is the second residence of the Ottoman Sultans, where they lived and ruled the empire. The Topkapi Palace must not be seen as the only private residence of the sultana and his court, and it was much more than. It was the seat of the supreme executive and judicial council of the Empire, the Divan. It housed the most selective school for the imperial civil service, the Palace School, Enderun.
The First Court, which was open to the public and was the service area for the Palace. It housed a hospital, bakery, an Arsenal, the mint and outer treasury, and many storages and dormitories for guards.
The Second Court was the seat of the Divan, devoted to the public administration of the Empire; anyone could enter who had business to transact with the Council. Apart from the Divan, the kitchen and privy stables were located.
The Third Courtyard, strictly reserved for the Court and Government officials, was given over to various chambers or reception rooms of the sultans.
The Forth Court is not a real court that some pavilions are located where you could see the Bosphorus over there.
The Harem was not an original part of the Palace as laid out by Mehmet. Sultan Mehmet seems to have designed Topkapi Palace as a kind of glorified office-building for the transaction of the Ottoman Empire’s public business and the Civil Service training. At all events, the earliest buildings in the Harem, which can be definitely dated, belong to the reign of Selim’s son and successor, Murat III (1574-1595).
The Topkapi Palace was converted into a museum in 1924 by M.K. Atatürk and opened to the public after a comprehensive restoration. The Palace houses many Ottoman and European works dating from the beginning and the end of the Empire, such as; Army and Arms Collection Room, Imperial Council, Clocks Collection, Kitchens, Throne Room, Library, Treasury Room with 86 carats diamond which is called Kasikci or Spoon Maker, Relics Room, pavilions and more things are awaiting fort he, visitors.