Istanbul is a city in Turkey that straddles Europe and Asia across the Bosphorus Strait. Historically, it was known as Constantinople and Byzantium. Currently, it is is the most populous city in Turkey and the country's economic, cultural, and historic center.

Istanbul is now a city that reflects cultural influences of the many empires that once ruled the land. In the Sultanahmet district, the open-air, Roman-era Hippodrome was for centuries the site of chariot races, and Egyptian obelisks remain. The iconic Byzantine Hagia Sophia features a soaring dome and Christian mosaics.

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