Coordinates: 55°42′40″N 37°37′45″E / 55.71111°N 37.62917°E / 55.71111; 37.62917

The Russian Orthodox Church (ROC; Russian: Русская Православная Церковь, Russkaya Pravoslavnaya Tserkov') headed by the Moscow Patriarchate (Russian: Московский Патриархат, Moskovskiy Patriarkhat, also known as the Orthodox Christian Church of Russia, is a body of Christians who constitute an autocephalous Eastern Orthodox Church under the jurisdiction of the Patriarch of Moscow, in communion with the other Eastern Orthodox Churches.

The ROC is often said to be the largest of the Eastern Orthodox churches in the world; including all the autocephalous churches under its umbrella, its adherents number over 150 million worldwide—about half of the 300 million estimated adherents of the Eastern Orthodox Church. Among Christian churches, the Russian Orthodox Church is second only to the Roman Catholic Church in terms of numbers of followers. Within Russia the results of a 2007 VCIOM poll indicated that about 75% of the population considered themselves Orthodox Christians. Up to 65% of ethnic Russians and a similar percentage of Belarusians and Ukrainians identify themselves as "Orthodox". According to figures released on February 2, 2010, the Church has 160 dioceses including 30,142 parishes served by 207 bishops, 28,434 priests and 3,625 deacons. There are 788 monasteries, including 386 for men and 402 for women.

Moscow ( /ˈmɒskaʊ/ or /ˈmɒskoʊ/; Russian: Москва́, tr. Moskva; IPA: [mɐˈskva] ( listen)) is the capital and the most populous federal subject of Russia. The city is a major political, economic, cultural and scientific center of Russia and the continent. Moscow is the northernmost megacity on Earth, the most populous city in Europe, and the 6th largest city proper in the world. Its population, according to the results of the 2010 Census, is 11,503,501. 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. Moscow is the site of the Moscow Kremlin, an ancient fortress that is today the residence of the Russian President and of the executive branch of the Government of Russia. The Kremlin is also one of several World Heritage Sites in the city. Both chambers of the Russian parliament (the State Duma and the Federation Council) also sit in Moscow.