First of all, there’s no such thing as the Trans-Siberian Express. What you do have are the Trans-Siberian railways which can take you from Moscow to all the corners of South East Asia including Vladivostok on the Pacific coast of Russia (with a boat going to Japan), Ulan Bator in Mongolia, Beijing or Shanghai in China (with boats going to south Japan) or even lines stretching down to Hanoi and Saigon.
We’re talking about 6000+ miles of train travel here which has to count as an adventure just for the mental strain of watching so much scenery go past. There’s every variety of train from slow locomotives filled with poor Chinese and Russians, to nippy trains with plenty of backpackers competing to spot the sights mentioned in their Trans-Siberian guidebooks.
It’s also about the cheapest way of getting to Asia that there is. A one way in the fancy 2 berth compartments may cost you around $650, $330 in a 4 bed carriage and about half of that in the lumpy third class carriages where you fight for what space you can.
Organising visas can be a bitch and trains have to be reserved which means you have to plan if and where you want to get off and make separate reservations accordingly. The rest of the time you play chess, read books and drink plenty of vodka. Get your one way ticket from the confines of modern Europe to the middle of nowhere.
Check out http://www.seat61.com/Trans-Siberian.htm – the ultimate trans-siberian railway guide.