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 was built in place of a 6th-century Byzantine church in Galata. This chapel was significantly enlarged in 1325 by the Dominican friars, who officially renamed it as the Church of San Domenico, but local residents continued to use the original denomination of San Paolo. In 1407, Pope Gregory XII, in order to ensure the maintenance of the church, conceded indulgences to the visitors of the Monastery of San Paolo in Galata. The building is known today as the "Arap Camii" (Arab Mosque) because a few years after its conversion into a mosque (between 1475 and 1478) under the Ottoman Sultan