Moscow is the capital of Russia, the largest country by land area in the world. It is the 8th most populous country though, with around 143 million people, making it one of the lowest population density countries. The population in and around Moscow make up most of the country's population. Moscow is the hub for the railroads, including the Trans-Siberian railroad built in 1891. Moscow is the center of government, with the Kremlin located in the very center of the city. St. Basil's, the onion-domed church next to the Kremlin is the center of the Russian Orthodox Church.