Over 3000 kilometres long, the Himalayas are China's real Great Wall.
With hundreds of peaks over 7,000 metres and 13 peaks higher than 8,000 metres,
they are the highest mountains on Earth.
The Tibetan region contains over 35,000 glaciers that cover over 100000 square kilometres.
They comprise the largest area of ice outside the polar regions
and nearly a sixth of the world's total.
These glaciers are the source of most of the water in the region.
And the Tibetan plateau is studded with glacial lakes.
At over 4,500 metres up,Lake Manasarovar in the far west of Tibet
is the highest freshwater lake in the world.