Having finally made it over the Myanmar-China border, Salopek is back on his feet, pacing across China’s Yunnan province.

In southwest Yunnan, alongside his walking partners Yang Wendou and Li Bing, he has been trekking through the gorges and mountain passes of the Gaoligong Mountains. Some of these paths were part of the historic southern silk road, a vital trade route between China and South East Asia. Salopek reports that it remains “a universe away from the throbbing Chinese coastal megacities” of today.

The Gaoligong Mountains are also an important biodiversity hotspot, with 5,000 species of plants and 700 animal species still clinging on here. "The planet’s biosphere, our ecological house, is tottering. It is losing its load-bearing beams," writes Salopek. For now, at least, southern Yunnan remains relatively untouched.