Istanbul Turkey's largest city and one of the biggest conurbations in Europe. A population of around 14 million is spread over north western Turkey in a transcontinental area that straddles the Bosphorus, marine straits that link the Black Sea with the Sea of Marmara. Istanbul's commercial and historic centres lie in Europe while about two-thirds of its population lives in Asia. Founded by the ancient Greeks in the 7th century BC as Byzantium, Istanbul has been the capital of the Byzantine, eastern Roman and Ottoman empires. Its main landmarks, such as the Hagia Sophia, once a church, then a mosque, now a museum and the Topkapi Palace, reflect this mixture of cultures. The city's Grand Bazaar, that has been functioning since the 15th century, is not only the largest covered market in Europe, it vies with numerous modern shopping malls to serve both locals and tourists.
Istanbul offers all types of hotel accommodation expected of a major cosmopolitan city. There are luxury five star and boutique hotels in the Old City, Sultanahmet, together with budget priced guest houses. There are renovated palaces and modern hotels of all classes along the Bosphorus shoreline outside the city.
Public transport within the city consists of rapid transit buses, metro lines, trams and funiculars. The O-1, O-2, O-3, O-4 motorways link Istanbul to the rest of Turkey and three of them, O-2, O-3 and O-4 link with the E80 European motorway network. Ataturk International Airport is located 15 miles west of the city while low cost carriers fly to Sabiha Gokcen International Airport 28 miles south east of Istanbul. The resumption of international rail services awaits the completion of major construction projects.