For centuries, people have been captivated by the Tibetan legend of 'Shambhala' - or 'Shangri-La' - a mystical earthly paradise hidden beyond the Himalayan mountains.

Today, Tibet is still one of the world's least-known places, and one with a rich tradition of unique culture and mythology. Known as the 'roof of the world' due to its breathtaking average height of 13,200ft (4,060m) above sea level, Tibet is home to more Himalayan peaks than anywhere else: Mount Everest lies on its border with Nepal.

As befits such a remarkable land, Tibet's capital Lhasa is home to an amazing UNESCO registered collection of spectacular palaces and temples. These include the Potala Palace, once the residence of the Dalai Lama, a unique building that includes, among other things,chapels, a library of scripture - and 10,000 shrines. Lhasa's temples and monasteries are key centres of Buddhist teaching.

Yet Tibet has been virtually inaccessible - until now. That only changed with the building of the awesome Golmud to Lhasa railway, which opened in 2006. More than 600 miles (960 km), over 80% of the railway is at an altitude of more than 13,000ft (4,000 m) and much of this magnificent line runs over permafrost. With the summit, the Tangula Pass, at 16,640ft, (5,072m) it is also the world's highest railway. To travel on it is a true pioneering adventure: an experience as unique as the places it takes us to.