The length of the railway is 1,956 km (1,215 mi). Construction of the 815 km (506 mi) section between Xining and Golmud was completed by 1984. The 1,142 km (710 mi) section between Golmud and Lhasa was inaugurated on July 1, 2006, by Chinese President Hu Jintao: the first two passenger trains were "Qing 1" (Q1) from Xining to Golmud, and "Zang 2" (J2) from Golmud to Lhasa.[1] This railway is the first to connect the Tibet Autonomous Region to any other province, which, due to its elevation and terrain, is the last province-level entity in mainland China to have a railway. Testing of the line and equipment started on 1 May 2006. Passenger trains run from Beijing, Chengdu, Chongqing, Guangzhou, Shanghai, Xining, and Lanzhou.The line includes the Tanggula Pass, which, at 5,072 m (16,640 feet) above sea level, is the world's highest railway. Tanggula railway station at 5,068 m (16,627 feet) 33°00′18.50″N 91°38′57.70″E is the world's highest railway station. 1,338 m (4,390 ft) Fenghuoshan tunnel is the highest rail tunnel in the world at 4,905 m (16,093 ft) above sea level. The 4,010 m (13,160 ft) New Guanjiao Tunnel is the longest tunnel and the culminating point 3,700 metres (12,100 ft) between Xining and Golmud and 3,345 m (10,974 ft). Yangbajing tunnel is the longest tunnel between Golmud and Lhasa. More than 960 km (600 mi), over 80% of the Golmud-Lhasa section, is at an elevation of more than 4,000 m (13,123 ft). There are 675 bridges, totalling 159.88 km (99.34 mi); about 550 km (340 mi) is laid on permafrost.