Thirty years ago during the Gulf War, former Special Forces soldier Chris Ryan was part of the ill-fated eight-man Bravo Two Zero SAS patrol in Iraq.
Deployed deep behind enemy lines, along the main supply route between Baghdad and north-western Iraq, the mission was to go badly wrong.
Three members of the patrol died and four were captured, with Chris the only one to escape Iraq.
Walking 190 miles to cross the border into Syria, it was the longest escape and evasion in the history of the SAS – and has become one of the most famous episodes of recent British military history.
Forces News spoke to him in St Martin's Church cemetery in Hereford, the SAS cemetery, where some of his colleagues are buried.
"We had very little information on the terrain, the weather, borders, anything," he said.
"In fact, my map dated back to 1944, the smock I was wearing was Second World War issue, so equipment was minimal.
"I can remember getting onto the helicopter and my QM [Quartermaster] was next to me and I said 'this is a one-way ticket'."
On arrival, Chris and his team found the ground was too hard to dig an observation post. He later found out that two sister patrols aborted the mission on arrival.
They were then discovered by a goat herder who informed the local militia and a firefight followed.
Chris and two others became separated from the rest of the patrol, with their only option to walk to the border.
"We only had two weapons ... I knew we were in a bad place," he told Forces News.
"I wasn't interested in the Iraqi army. I knew the problem we were going to have is the cold and the weather."
As they set out to start walking, temperatures dropped so low it snowed.
Sergeant Vincent David Phillips and Trooper Steven John "Legs" Lane both died of hypothermia.
"I was with Vince as he was dying and I tried everything to convince him to keep moving," Chris said.
"It was just a disaster. The main enemy was the weather."
Chris subsequently lost contact with the group, so was alone in enemy territory.
"It was seven days without food and the last three days without water.
"I'd actually drank some water that was from a chemical plant and was full of effluent which burnt my mouth.
"So for the last three nights I had nothing and I was walking about 40km a night.
"I started hallucinating and seeing visions of my daughter. It was that vivid I was putting my hand out to get a hold of her and she was talking to me."
After seven days and eight nights on the run, Chris eventually made it to the Syrian border town of Abu Kamal after walking 300km.
"I had cold injuries, I'd lost 38lbs in weight, I had no toenails, there was pus coming out of all the areas that had blistered, I had bedsores and a damaged liver."
The Syrians eventually handed Chris to the British Embassy and he was taken home.
Thirty years on, Chris says he is not bitter about the experience, saying: "It's war, the fog of war, the confusion of war, we were getting out there to get into a scrap.
"Yes, mistakes were made but one thing with the regiment is they try to learn from mistakes.
"There wouldn't be any more young men having to walk seven days and eight nights, so you've got to take the positive side.
"When it goes wrong with the SAS, usually it goes tragically wrong.
"That's what happens when the Special Forces make mistakes, usually the cost of life is very high."
Listen to the story of the First Gulf War, told by those who were there. Decision-makers, military commanders, soldiers, sailors and air personnel reflect on their roles in the conflict, 30 years on.
'GRANBY: The Storm in the Desert' is available from Friday 15 January, wherever you get your podcasts and on bfbs.com/podcasts.