The Chengdu-Lhasa Highway, also called Sichuan-Tibet Highway for short, is a modern upgrade of the ancient Sichuan-Tibet Highway. It starts from Chengdu, the capital of Sichuan Province in the east, and ends at Lhasa, the capital of Tibet in the west. It's part of the sections of National Highway 318, 317, 214, and 109. It is the most difficult road in China. Divided into north and south routes. Some connecting lines in the middle of the north-south routes are generally classified as part of the Sichuan-Tibet Highway.
As one of the major roads in and out of Tibet besides Qinghai Tibet Railway, this highway was inaugurated and was made functional on 25th December 1954. This highway is vital to the progress of Eastern Tibet, by promoting the economic development of Eastern Tibet. This road is known to be the best option to reach Tibet if you are coming from Sichuan or any other Southern Chinese Province by the overland route.