Russia is (by far) the largest country in the world. Population density outside the few major cities (Moscow, St. Petersburg) is very low. Siberia is almost "empty". The best way to see the place is either by a) taking a really, really long vacation or b) taking the Trans-siberian Railway fro Vladivostok to Moscow covering 5 time zones and 11000 kilometers.
For practical (touristic) purposes we split up Russia in 2 parts: 1) Russia in Europe and 2) Russia in Asia.