Moscow ( /ˈmɒskaʊ/ or /ˈmɒskoʊ/; Russian: Москва́, tr. Moskva; IPA: [mɐˈskva]) is the capital and the most populous federal subject of Russia. The city is a major political, economic, cultural and scientific center in Russia and on the continent. Moscow is the most northern megacity on Earth, the most populous city in Europe, and the 6th largest city proper in the world. It's also the largest city in Russia. Based on Forbes 2011, Moscow has the largest community of billionaires in the world.
Moscow is situated on the Moskva River in the Central Federal District of European Russia. In the course of its history the city has served as the capital of a progression of states, from the medieval Grand Duchy of Moscow and the subsequent Tsardom of Russia to the Soviet Union.