Home to mythical kingdoms, wars and expeditions, and strange and magical beasts, the Himalayas have always loomed tall in our imagination.

Overrun at different times by Buddhism, Taoism, shamanism, Islam and Christianity, they are a grand central station of the world's religions. They are also a plant hunter's paradise, a climber's challenge, and a traveller's dream.

In his quest to explore the region's seismic history, Twigger seeks out the Nagas, who helped his grandfather build a camp for Allied soldiers near Imphal during the Second World War and takes the most scenic bike ride in the world from Lhasa to Kathmandu.

The result is a sweeping, fascinating and surprising journey through the history of the world's greatest mountain range.