Istanbul is the largest city in Turkey, forming the country's economic, cultural, and historical heart. With a population of 13.4 million, the city is at the center of the second-largest urban area in Europe after Moscow, and among the world's largest cities by population within city limits. Istanbul's vast area of 5,343 square kilometers (2,063 sq mi) is coterminous with Istanbul Province, of which the city is considered capital.