Kiev is the capital and the largest city of Ukraine, located in the north central part of the country on the Dnieper River. As of April 2007, official municipal estimates placed the population of Kiev at about 2.7 million inhabitants, although some much higher unofficial estimates are often published. Kiev is an important industrial, scientific, educational and cultural centre of Eastern Europe. It is home to many high-tech industries, higher education institutions and world-famous historical landmarks. The city has an extensive infrastructure and highly developed system of public transport, including the Kiev Metro.