Istanbul
Marmara, Turkey 144 tours visit here
Istanbul is Turkey's largest city and cultural centre, spread along both banks of the Bosphorus and split between Europe and Asia. Founded as the Greek colony Byzantium, it became Constantinople, capital of the Roman and Byzantine empires and later of the Ottoman Empire. Ankara is the national capital, but Istanbul remains the country's commercial heart and busiest gateway for visitors. Most sightseeing is concentrated on the UNESCO-listed historic peninsula, where Hagia Sophia, the Blue Mosque, Topkapi Palace, the Basilica Cistern and the Grand Bazaar all lie within walking distance around Sultanahmet. Across the Golden Horn, Galata Tower and Istiklal Street mark the denser, more modern Beyoglu district, while the Asian side around Kadikoy and Uskudar is quieter and more residential. Ferries across the Bosphorus are part of daily life and the easiest way to see the waterfront palaces, mansions and fortresses along the strait. The main monuments are usually covered in two or three days on foot and by tram. Hagia Sophia and the Blue Mosque are working mosques, so visits pause around prayer times and modest dress is expected; spring and autumn bring the mildest weather.