Tanglang La is the second highest of the great passes on the road between Manali and Leh, at about 5,300 metres, and it is a place where the air is so thin that walking up a few steps feels like climbing a stair. The pass lies on the watershed between the Indus valley and the high plateau to the south, and the landscape around it is stark and vast: bare ridges of brown and grey, snowfields in the shadows, and a sky that looks very dark and very close.
The ride up from the south crosses the Morey Plains, a high, flat desert at nearly four and a half thousand metres, which is an astonishing place in itself. The road runs across it in long, straight lines, with the surface sometimes smooth and sometimes broken, and the mountains standing at the edges like the walls of a vast amphitheatre. Then the road begins to climb in a series of bends to the summit, where you will find a signboard, a heap of prayer flags and perhaps a few other riders taking photographs.
On the north side, the road drops steeply towards the Indus, passing the village of Rumtse, where the first green returns. Leh is roughly a hundred kilometres from the pass, and the descent into the valley is a long, welcome relief to the lungs. The road here is generally good, with big curves and open views, but be ready for sudden gusts of wind and the odd landslide.
Practical matters are serious at this height. Tents at Pang, on the southern approach, offer simple meals and a bed, but they are basic and the nights are bitterly cold. Spend a few days in Leh before attempting the pass, drink lots of water and stay a short time at the summit, because altitude sickness is real and can strike without warning. The season runs from June to September, and the pass can close at any time with snow.