Tourism in Turkey 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 Sultan Ahmed Mosque (the "Blue Mosque"), the Hagia Sophia, the Topkapı Palace, the Basilica Cistern, the Dolmabahçe Palace, the Galata Tower, the Grand Bazaar, the Spice Bazaar, and the Pera Palace Hotel. Istanbul has also recently
Galata (Pera) in Istanbul, and is known as Karaköy. There are several theories concerning the origin of the name "Galata". The Greeks believe that the name comes either from "Galatai" (meaning "Gauls"), as the Celtic tribe of Gauls (Galatians) were thought to have camped here during the Hellenistic period before settling into Galatia in central Anatolia; or from "galatas" (meaning "milkman"), as the area was used by shepherds for grazing in the Early Medieval (Byzantine) period. Italians believe the name comes from "calata" meaning slope or descent, because Galata, which is a former Genoese colony, is located on a hill that