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
Stone City used for naval training by General Zhou Yu (175-210). On a political visit to the area, the prime minister of the Shu Kingdom, Zhuge Liang (181-234) described the Qingliangshan Hill and Stone City area as "Zhongshan curling like a dragon and the Stone City crouching like a tiger". The stone wall is all the remains from the ancient city. The ancient city is strongly enough associated with Nanjing that Nanjing itself is sometimes referred to as "Stone City". One of the most famous of its landmarks is the "Ghost-Faced Wall". The ancient city wall from Caochang Gate () to Qingliang