Dear Percy Cheung:
Warmly greetings from Top China Travel! Many thanks for your enquiry and trust to us!
I am Lily, the sales reprehensive of TCT. It is my pleasure to assist your trip to China!
During summer time, it is very easy to get landslides, while winter time, it is with heavy snow. So the best time to take this trip is Spring and Autumn.
The overland route is by road from Zhongdian in northern Yunnan. The Chinese government is promoting tourism by calling the area around Zhondian Shangrila. The road condition has greatly improved over the years but you still need a four wheel drive vehicle. This southen road is extremely scenic with snowcapped mountains, alpine lakes and gorgeous scenery. Several companies offer tours on this route. We here would like offer you the best route by land tranfer from Shangri-la (Zhongdian) to Tibet takes 7 days. Please advice your estimated travelling month and group size / hotel request so that we can go ahead to quote for you.