“Kremlin” is the Russian word for citadel and refers to any major fortified central complex found in historic Russian cities. But the best-known one is the Moscow Kremlin, located on a hill above the Moscow River. It began life in the 1150s, Ivan the Great was responsible for the most ambitious modifications, and during the period of 1475-1516 Italian architects were brought in to build new fortified walls and a number of cathedrals. Today, The Kremlin includes palaces, cathedrals and the enclosing Kremlin Wall with Kremlin towers. The former residence of  Tsars serves since the beginning of the 20th century as the official residence of the President of Russia.