Istanbul is Turkey’s most populous city, and its cultural and financial center. Istanbul population is estimated to between 12 and 19 million people, making it also one of the largest in Europe and the world. The city was one of three European Capitals of Culture in 2010. Istanbul is divided by the north south Bosphorus Strait, the dividing line between Europe and Asia, the estuary of the Golden Horn bisecting the western part and the Sea of marmara, forming a boundary to the south. 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, Beyoglu and Taksim, the heart of modern Istanbul, while Kadikoy is 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 winter.
Istanbul's public system can be difficult to figure out, maps are rare and you often have to transfer, and pay another fare, to get where you going. Each time you use a tram, metro, bus or boat on the public transport system, you will need to use a token, which can be bought at various ticket kiosks and machines at bus, rail or metro stations. Only cash in Turkish lira us accepted, no credit cards or foreign currency. Also be aware that the Istanbul subway system does not offer transfer tickets and as such each new line requires a new fare, unless you use and Istanbulkart or Akbil. Taxis are the easy and cheap way to get around.