An air ticket from Chengdu to Lhasa should be around RMB 1660 (GDP 153 or around), including tax and fuel surcharge. But this price is subject to change, of course.
11
losang
It sounds like you were going off travel advice that was from before March 2008. Since then, travel in Tibet has changed dramatically. This forum as well as the newest edition of Lonely Planet's Tibet guidebook has detailed information about travel to Tibet. The days of going to Lhasa with just a travel permit are long, long gone. All foreigners MUST be part of an organized tour that includes travel permits, a tour guide and a private vehicle with a driver (no vehicle is needed if you plan to stay only in Lhasa).
For more information on travel to Tibet, read through the following:
Getting to Tibet
Pro tip
Lonely Planet
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