Image copyright Stephen Fabes

Stephen Fabes, a junior doctor from London, has spent six years cycling round the world. He has slept in schools, in police stations, in churches, mosques, monasteries and in army barracks - and thinks the world is a much better place than we are led to believe.

Twenty-five tyres, 12 bicycle chains and two saddles - that's how many times you can expect to change parts on a bicycle when cycling 86,000km (53,000 miles) around the world.

And you'd better be ready to mend about 200 punctures.

Stephen Fabes has cycled across six continents from Europe to the Americas, from Africa to Asia - all on his bike, with the exception of intercontinental flights.

We met in the Georgian capital Tbilisi, as he was preparing to pedal his way home. He had made a big loop of the country and pronounced it one of the most beautiful he had visited.

"There was a five-day window when trees change colour and I was in Svaneti, north-western Georgia. It was incredible. I've never seen anything like that - entire mountains rust-coloured, it was great."

Image copyright Stephen Fabes Image caption The stunning beauty of autumn in Georgia

In a few days he plans to end his journey back where he started - at St Thomas's Hospital in London, where in 2010 he waved good-bye to his colleagues and set off.

On that first day he almost ended up quitting. His first stop was a local pub.

"I cycled to the George, a pub where I had the idea to go travelling. I invited my friends and after several hours of drinking was thinking of maybe going back to my flat, which was round the corner, and start the cycling the following day, but friends persuaded me to stick to the plan," he says.

Image copyright Stephen Fabes Image caption Outside St Thomas's Hospital in January 2010

Depending on the season, he has usually travelled between 40km and 100km (25 and 62 miles) per day, and lived comfortably on less than $10 (£7) per day, including accommodation.

His initial purpose was to raise money and awareness for the British charity Merlin (Medical Emergency Relief International) but he began to take an increasingly strong interest in the marginalised people he came across on his route.

"I felt that I can learn about the mainstream society by looking and studying the people who live on the edge of society," he says.

He got involved in non-profit healthcare projects in Asia, including a floating medical clinic in Cambodia, and a TB clinic on the border between Thailand and Myanmar.

Image copyright Stephen Fabes Image caption A floating clinic on a lake in Cambodia

"Non-governmental organisations were not working much inside Myanmar at the time, so refugees would come across the river, they were members of the Karen community ostracised because they had HIV and they often would be treated in this clinic," he says.

"I remember seeing a woman who was dying - completely emaciated. She had hours or days to live, and next to her was a Buddhist monk. She'd been left at the monastery, and he was told to leave the monastery to look after her."

In Kathmandu Fabes joined a mobile clinic treating street children addicted to glue-sniffing.

"They were aged seven to 18, they would get glue from local shopkeepers who would sell it at a higher price because the kids were addicted to it. Most of them are orphans and they live together in the street."

Image copyright Stephen Fabes Image caption The Cordillera Blanca mountain range, Peru

Also in Kathmandu, in a hospital for leprosy patients, he met a young woman whose life was changed by wind-up radios distributed by NGOs for education purposes in remote parts of Nepal.

"She had no fingers and no toes and was locked up by her family. She had one of those radios and was listening to a programme about leprosy and realised that maybe that's what she had. She asked her brother to carry her for four hours to the nearest road, and then eventually got to hospital."

I asked about the dangers he had encountered.

"People are often worried about abduction and dangerous diseases but the biggest risk by far is being hit by a car. I knew people who were killed - a British couple in Thailand. A lot of cycle tourism died recently because of that," he replied.

Image copyright Stephen Fabes Image caption Cycling through the Northern Cape in South Africa

One of Fabes's scariest experiences was the sight of a gun poking through his tent in the middle of the night in a remote part of Peru.

"A guy aimed the gun at me and told me to get out. He marched me into his house, it was raining very hard and his was the only house in the area and it looked empty," he says.

"I noticed that he looked very nervous. Eventually he put his gun down. He had been robbed a month before and thought I was associated with the robbers. About 20 minutes later he made me soup."

Going through steppes or deserts, where landscapes did not change for days on end was the hardest part, he says. But he dealt with it by listening to music, or just thinking.

Image copyright Stephen Fabes Image caption The Salar de Uyuni salt flat in Bolivia

"Some of the blogs were written in my head, I enjoyed this space to think, it is a bit of luxury," he says. "I did not have much time to think when I was in London, and that's what I really relish about this journey."

Fabes has experienced extremes of climate, including a mid-winter journey through the bitter cold of Mongolia.

"There are no hostels once you get outside [the capital] Ulan-bator. It was a very cold winter which the Mongols call 'zud', when all the animals die. I had three sleeping bags and three sleeping mats, but the problem was my water, which froze. If your water freezes it does not defrost because in the day the temperature was -12C (10F). I was constantly trying to keep water next to my body."

Image copyright Stephen Fabes Image caption Camping on Lake Khovsgol in Mongolia

Cycling through Central Asia, Fabes recalls being searched for hours by border guards in Uzbekistan, a country known for its poor human rights record.

"They were looking for pornography, going through every film on my laptop. They found George Orwell's 1984, which has some sex scene in it, and they were looking at it on big screen. And I thought to myself: 'I can't get arrested for having a film about totalitarianism in Uzbekistan.'"

Image copyright Stephen Fabes Image caption A young woman and her baby in Myanmar

Fabes plans to write about his adventures and what he has learned on his journey.

His biggest discovery, he says, was finding that the world is a friendlier and more welcoming place than he thought.

"I have had a very positive impression of the planet and that bolsters my faith in humanity. When you are travelling by bicycle the universe is on your side, you get lots of offers of hospitality.

"Just the number of time strangers brought me to their homes to feed me, it happens everywhere, even in miserable England. On my first night a lady in Kent offered me to stay in her home." `

Image copyright Stephen Fabes Image caption Fabes received a warm welcome across the world, including Uganda

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