Words by: Kieran Alger

Ask anyone who’s run the world famous Marathon des Sables – a six-day, 250km ultra across the Moroccan Sahara – what they enjoyed most and they’ll tell you the campsite camaraderie tops the epic views and wild desert dunes.

Each open-sided tent on the bivouac becomes home to eight people and during the days spent sleeping sardined inside, sharing the joy and pain, highs and lows, strangers become lifelong friends. Your tent mates become the life force that gets you up to the start line every morning and carries you to the finish line every evening. In the face of adversity, you become an unbreakable team.

So it was a big shock when three years after we all finished the Marathon des Sables one of our eight, Sam, revealed that he had been diagnosed with Stage 4 bowel cancer. Still in his thirties with a young family, Sam was facing the challenge of his life and I had this feeling that – just as we had done in the desert – we should do something to show him his team was with him.

I had an idea. I sent an email to the Marathon des Sables group saying: “Hey guys, do you know the Thames is 184 miles long? Who wants to run it?” Within minutes, one of our eight, Fabrice, had replied and thrown his hat into the ring. By the end of the day, three others had signed up. And the challenge to run the length of the great River Thames, approximately 184 miles from its source to the Thames Barrier was born.

We’d run in support of Sam and to help raise money for the charity he’d been raising money for, Children with Cancer.

The Thames snakes from its source in the west of England in Gloucestershire, via famous towns and cities like Oxford and Henley, past the former home of King Henry VIII at Hampton Court Palace and through London out to the Thames Barrier beyond Greenwich, the home of time.

Less than two months later, after a couple of us were sidelined with injuries, three of us laced up our trail shoes, clipped on our ultra vests and started an epic journey along this historic river. Here’s what happened.

Photos by: James Carnegie

Thames Source to Sea: the stats

• 190 miles run
• 7.25 marathons in 3 days
• 60 hours overall
• 44 hours of running
• 9.5 hours sleep
• 14 min/miles average running pace
• 343,717 steps
• 23,890 calories burned