Ben Fogle came close to death after two oxygen tanks exploded while he was scaling Mount Everest.
Ben Fogle
The 44-year-old TV presenter felt as though he was going to "die straight away" as soon as the second tank blew up during his expedition up the world's highest mountain, and admitted it was a "pretty scary" time.
He said: "It's a big question looming over Everest this year because it wasn't just us, there's a problem with the equipment and lots of teams were forced to pull out.
"When you're up at that height, it's pretty scary. As you're on the famous Hillary step, when the second tank exploded, your mind imagines you're on Mars and if it goes you're just going to die straight away."
Ben now describes the incident as the "main blight" of the trip, and counts Everest as the most "terrifying" place he has ever visited, as well as being the "most beautiful".
Speaking on 'Good Morning Britain', he added: "People climb without oxygen but my body hadn't fully acclimatised.
"It was the main blight on the expedition, but the silver lining is I not only survived, I stood on the roof of the world.
"It's the most beautiful, terrifying place I've ever been."
Last week, Ben paid tribute to his stillborn son Willem, who he and his wife Marina tragically lost in 2014, as he reached the peak of the mountain.
He wrote on Instagram: "I gave an assembly to my children's school today via satellite phone. Nothing has given me as much pleasure so far on this trip than inspiring and exciting 300 young children, particularly my two beautiful children Ludo and Iona. It gives me so much happiness to share this journey with so many others. I don't feel alone here. Never. There is a spirituality but I can also feel the support and the love here on Instagram ... There is one person in particular for whom this journey is dedicated. A little boy called Willem Fogle. He was my little son. Stillborn at 8 months. A little boy I never got to know. A little life that never got to live. A breath that was never exhaled. His loss changed our lives and I think about him daily. Losing my little boy made me reevaluate life. Not only do we hold our two beautiful children closer to us but it was a reminder to live life for the now. Don't waste it. Cradling little Willem to say goodbye, I made a promise to him to live my life brightly. To embrace everyday. To always smile. To be positive and to inspire. In some ways I am now living my life for two. Willem is always there. I think he is my guardian angel here. There is one particular star that shines brighter. It draws my attention. It reflects off the snow and ice. I feel so lucky. I will never take life for granted but above all I'll never be alone #everest2018 [sic]"
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