How ex-Monty Python comic Michael Palin became an accidental traveller when he accepted an offer to go around the world in 80 days, following the route of Phileas Fogg in the classic Jules Verne story. He looks back on the programmes and his diaries to reveal how the series was made and the impact it had. And fans and friends including Sir David Attenborough, Joanna Lumley and Simon Reeve reflect on his achievements. Little did he know the resulting series would become a huge hit, changing the face of TV travel programmes.

This episode explores how the success of Around the World in 80 Days opened the door for Michael Palin to tackle an even more ambitious journey for his next series. In Pole to Pole, Michael followed the line of 30-degree-east longitude from North Pole to South, an incredibly challenging route across the USSR, Africa and finally Antarctica.

In his third series, Michael Palin took on his most ambitious journey yet - a 50,000-mile route around the Pacific Rim, taking in Russia, China, Vietnam, Australia and New Zealand and North and South America. This huge undertaking stretches him and the crew to their limits, and it sees Michael adopt a more investigative role as he seeks to get under the skin of the places he visits - from a booming South Korea to Colombia with its drug wars and poverty.

Michael revisits his fourth - and in some ways, most personal - travel series. Inspired by the apparent emptiness of the Sahara Desert as seen from a flight and by boyhood dreams of exploration, Michael sets off to find out what this 'blank space' contains. He is delighted and inspired by the societies he encounters there - nomads, refugees, artists. He also confronts some harsh realities - the effects of war, the migrant crisis and the rise of militant Islam. From Gibraltar, Michael looks across the Mediterranean to what is for him a mysterious land - North Africa. Inspired by the apparent emptiness of the Sahara Desert as seen from a flight and by boyhood dreams of exploration, Michael sets off to find out what this 'blank space' contains. He is delighted and inspired by the societies he encounters there - nomads, refugees, artists. He also confronts some harsh realities - the effects of war, the migrant crisis and the rise of militant Islam. From Gibraltar, Michael looks across the Mediterranean to what is for him a mysterious land - North Africa.

Michael travels the Himalaya through Pakistan and India, meets the Dalai Lama, then battles altitude sickness to reach the base camp at Annapurna.

Continuing his Himalayan journey, Michael reaches Everest base camp. Then, he meets a Yak herder, and explores Bhutan before descending to Bangladesh.