The road south from Golmud climbs steadily for a hundred and sixty kilometres into the Kunlun range, topping out at the Kunlun Mountain Pass at 4,768 metres. A modest stone marker and a small Buddhist shrine sit at the col. There are usually a few stalls selling tea and yak jerky, and an obligatory photo opportunity with a yak.
The pass is the gateway to the Tibetan plateau proper. South of here the road runs along a long stretch of high, treeless grassland — the Hoh Xil — before climbing again to Tanggula and dropping into Tibet. Most travellers cross it by sleeper bus or by car in a few minutes; do not stay if you are feeling the altitude.