Tibet railway starts from Golmud, the next station of Xining. So all the trains to Lhasa, including Beijing, Shanghai, Guangzhou and Chengdu meet at Lanzhou and Xining, and continue the trip for about 24 hours onto Lhasa. From 2018, high-speed railway reaches Lanzhou and Xining, then many people choose to take bullet train or flight there to make the train ride short and more comfortable. On the other hand, tickets from Beijing are also very difficult to book due to rare availability. So we are only able to guarantee the tickets for groups booked tour with us. If you start the tour from Beijing, we still recommend you take bullet train from Beijing to Xining, then Xining to Lhasa.