I live in the biggest country in the world. So all means of transport are available in Russia . In my opinion traveling by train is the best way. Of course it's not the quickest way. The quickest one is plane. But I'm afraid of flying. So for train is the most convenient. The territory of the Russian federation is vast . So when you travel by train you can have a sleep or snack during your trip. But you can't do that at other means of transport. In other words you feel on train like you are at home. Plus you can have a nice talk with fellow traveler.