Thank you for your info on buying trains tickets. I am planning to take the train from Dunhuang to Jiayuguan on April 13th, 2011 and from Jiayuguan to Lanzhou on April 15th. I will fly to Beijing on March 29th. Should I order these tickets now, before I leave for Beijing? I afraid that if I order these tickets 10 days before the departure day, which means that I will have to order them in Beijing where I might not have access to internet. I've already made reservation in the two cities.

Also, I would like to take a day trip from Beijing to Shanghaiguan. Should I buy the tickets on the day of the trip, or should I buy in advance? I heard that the tickets from Shanghaiguan to Beijing are not easy to get because this journey is very crowded. Thank you very much for your time.