James Le Gallez has completed the Marathon des Sables, known as the "toughest footrace on earth".
The 253 kilometer (157-mile) course across the Moroccan Sahara took James Le Gallez 51 hours and 45 minutes to complete.
He placed 458 out of 842 runners.
James says it was the hardest thing he has ever done.
"Nought point one percent of the world's population will ever do a marathon, a fraction of that will ever do an ultra.
They require a lot more effort, but they are so much more fun.
They have scenery, the trails, the elevation - it's a completely different ball game"
He had several blisters, an ankle injury and temperatures up to 46 degrees Celsius to deal with.
James says he would encourage anyone to push themselves and do things they once thought were impossible.
"I saw a documentary about the marathon 10 years ago, and I thought it was cool, and never forgot about it.
The strap line at the time was 'the toughest footrace on earth' and I thought how cool would it be to say I had completed that."
James is still trying to reach his fundraising goal of £10,000 for three Channel Island charities: Autism Guernsey, the Guernsey Society for Cancer Relief and Jersey Hospice Care.
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