Istanbul is the most populous city in Turkey and historically known as Byzantium and Constantinople besides it is the economic, cultural and historic centre of the country. Istanbul is one of the world's most populous cities, ranking as the world's fourth-largest city proper and the largest European city and also the administrative centre of the Istanbul Metropolitan Municipality.
The strategic position of the city on the historic Silk Road, rail networks to Europe and the Middle East, and the only sea route between the Black Sea and the Mediterranean have produced a cosmopolitan populace. Approximately 12.56 million foreign visitors arrived in Istanbul in 2015, five years after it was named a European Capital of Culture, making the city the world's fifth most popular tourist destination.
The city's biggest attraction is its historic centre, a UNESCO World Heritage Site, and it’s cultural and entertainment hub is across the city's natural harbour, the Golden Horn, in the Bayou district. As a global city Istanbul has one of the fastest-growing metropolitan economies in the world. It is holding the headquarters of many Turkish companies and media outlets and accounts for more than a quarter of the country's gross domestic product.
Istanbul is one of the most important tourism spots not only in Turkey but also in the world. There are thousands of hotels and other tourist oriented industries in the city, catering to both vacationers and visiting professionals.
Turkey's largest city and metropolis and a leading global city, Istanbul, has a number of major attractions derived from its historical status as capital of the Byzantine and Ottoman Empires. These include the Suleymaniye-Mosque, Topkapi-Palace, Aya Sofya, Basilica Cistern, Yedikule Fortress, Blue Mosque, Chora Church, Dolmabahce Palace, Galata Tower, Istanbul Archaeology Museum, Museum of Turkish and Islamic Arts, Hippodrome.