The Topkapı Palace is a large palace in Istanbul, Turkey, that was one of the major residences of the Ottoman sultans for almost 400 years (1465–1856) of their 624-year reign. As well as a royal residence, the palace was a setting for state occasions and royal entertainments. It is now a museum and as such a major tourist attraction. It also contains important holy relics of the Muslim world, including Muhammed's cloak and sword.

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