THE 1776km high-speed line from Lanzhou to Urumqi in the Xinjiang region of northwest China must rank alongside the Qinghai Tibet Railway as one China's greatest engineering achievements of recent years. The 31-station line crosses the Gobi desert and the Qilian Mountains, reaching a summit of 3607m above sea level in the Qilianshan No 2 Tunnel, making it the world's highest high-speed line.