Built 1776-78, the triangular exterior surrounds a large courtyard divided into three parts, and the Senate attains a perfect harmony with the other Kremlin buildings around it. The Senate's facades are marked by the spirit of early classicism, and have little superfluous decoration. After the 1917 revolution, the building was used by the Soviet Government for meetings of the USSR Council of Ministers, and also contained the private study used by both Lenin and Stalin, under which a secret passage was later discovered and, it is speculated, may have been used by Beria to listen in on confidential conversations. The building has, since 1991, been the official residence of the President of the Russian Federation.