The Tanggu La or Tanggu Pass is a wide mountain pass over 5000 meters elevation in the People's Republic of China used by the Qinghai–Tibet Highway and Qinghai–Tibet Railway to cross the Tanggula Mountains. These mountains form part of the watershed separating the Yangtze River to the north and a zone of endorheic basins with internal drainage to the south. They also separate Tibet Autonomous Region and Qinghai Province.
The Qinghai–Tibet Highway reaches its highest elevation, 5,231 meters (17,162 feet) in Tanggu Pass. On August 24, 2005, rail track for the for the Qinghai–Tibet Railway was completed 28 kilometers to the WNW of the highway, reaching 5072 meters (16,640 feet). Tanggula Railway Station 1 km from this summit is—at 5,068 meters—the world's highest, 255 meters higher than Cóndor station, Peru.
The Qinghai-Tibet railway connects Xining, Qinghai Province to Lhasa. The 1,080-kilometre (670 mi) section from Golmud to Lhasa was opened on July 1, 2006. The rail cars have personal oxygen supplies to prevent altitude sickness.For a satellite image showing the separate highway and railroad routes over the pass, click here:. The rail route is highlighted in grey, with the 5,072 meter summit at the + crosshairs. The highway route is highlighted in yellow, with the 5,231 meter highway summit inside the largest box symbol.