By the mid 1500s, Istanbul, with a population of almost half a million, was a major cultural, political, and commercial centre.
Ottoman rule continued until it was defeated in WWI and Istanbul was occupied by the allies.
When the Republic of Turkey was born in 1923 after the War of Independence, Kemal Atatürk moved its capital to the city of Ankara.
Most sights are concentrated in the old city on the peninsula of Sultanahmet, to the west of the Bosphorus between the Horn and the Sea.
Across the Horn to the north are Galata, Beyoğlu and Taksim, the heart of modern Istanbul, while Kadıköy is the major district on the comparatively less-visited Anatolian side of the city.
The Black Sea forms the northern boundary of Istanbul.
Istanbul has a temperate oceanic climate which is influenced by a continental climate, with hot and humid summers and cold, wet and occasionally snowy winters.
Istanbul (Turkish: İstanbul) is Turkey's most populous city as well as its cultural and financial hub.
Located on both sides of the Bosphorus, the narrow strait between the Black Sea and the Marmara Sea, Istanbul bridges Asia and Europe both physically and culturally.
Istanbul's population is estimated to be between 12 and 19 million people, making it also one of the largest cities in Europe and the world.
Sultanahmet-Old City Essentially the Constantinople of the Roman, Eastern Roman/Byzantine, and much of the Ottoman periods, this is where most of the famous historical sights of Istanbul are located.
Princes’ Islands An excellent getaway from the city, made up of an archipelago of nine car-free islands—some of them small, some of them big—with splendid wooden mansions, verdant pine gardens and nice views—both of the islands themselves, and also on the way there.