The term 'Kremlin' is a CITADEL located in Moscow, Russia. It is the official residence of the President of the Russian Federation and has been the center of the government of the Soviet Union since the 14th century. The term 'Kremlin' is also used to refer to the nerve center of the Soviet Union, which was located in Moscow. This nerve center was responsible for the coordination of all government activities and was the headquarters of the Communist Party of the Soviet Union.