Baikonur (Kazakh: Байқоңыр, Bayqoñır ; Russian: Байконур, Baykonur), formerly known as Leninsk, is a city in Kyzylorda Province of Kazakhstan, rented and administered by the Russian Federation. It was constructed to service the Baikonur Cosmodrome and was officially renamed Baikonur by Russian president Boris Yeltsin on December 20, 1995.