Moscow is the capital city and the most populous federal subject of Russia. The city is a major political, economic, cultural and scientific center in Russia and in Europe. According to Forbes 2011, Moscow has the largest community of billionaires in the world. Moscow is the northernmost megacity on Earth, the second (after Istanbul) most populous city in Europe, and the 6th largest city proper in the world. It's also the largest city in Russia with a population, according to the 2010 Census, of 11,503,501. By its territorial expansion on July 1, 2012 southwest into the Moscow Oblast, the capital increased its area 2.5 times; from about 1,000 square kilometers (390 sq mi) up to 2,500 square kilometers (970 sq mi), and gained additional population of 230,000 people.
Over time, Moscow has acquired a number of epithets, most referring to its size and preeminent status within the nation: The Third Rome, The Whitestone One, The First Throne, The Forty Forties. Moscow's architecture is world-renowned. Moscow is also well known as the site of Saint Basilís Cathedral, with its elegant onion domes, as well as the Cathedral of Christ the Savior and the Seven Sisters.