The Birmingham-born TV presenter was in a coma for two weeks in September 2006 after the jet-powered Vampire car he was driving for Top Gear crashed at 319mph when a tyre burst.
He suffered serious head injuries and he was in hospital for five weeks before returning home to his wife Mindy and their two daughters, Isabella and Willow where he continued to recover from his frontal lobe brain injury.
Now, Hammond has shared a video on TikTok filmed in the Lake District at a tree he dreamed about while in his coma. In the emotional video, the 52-year-old recalls a dream that took him to his favourite place and has brought him huge comfort ever since.
In the dream, which he described as "really, really, really vivid", Hammond had been walking the hills of the Lake District overlooking Buttermere.
"In my mind I'd been walking these hills here in the Lake District. I was having a lovely time, strolling along, and gradually I got a sense of when you know you're in trouble," he explained. "That feeling grew and grew, and I walked up this slope where I am now towards this exact tree.
"And as I got closer and closer that sense of 'oo, I really am in trouble, I'm going to be shouted at, I'm going to be in a lot of trouble' grew and grew until eventually in my dream I turned back, I didn't walk round this tree and carry on.
"And I woke, and that's the dream I told Mindy about.
"Mindy told me her side of the story, because at the same time she had been called into the intensive care unit and that things were not looking good. I was on full life support and breathing support, the lot, and they said 'it's not looking good, we think we're going to lose him'."
Upon hearing the news, Mindy asked if there's anything she could do to save her husband. When they said 'no, not really', she asked to shout at him, to which they said yes, before they clarified: "No, I mean really shout at him."
"And she did," Hammond said. "And apparently she roared and screamed and swore at me 'don't you dare die', and that's when I turned from this tree in my dream and that's when I woke."
Hammond says that although he didn't physically walk up to the tree as he was in a coma in a Leeds hospital, his mind did, and his mind "is who I am".
But he takes "huge solace" because his "last thoughts" took to somewhere 'he loves, and is happy'.
"And that last thought, if I had shut down and stopped, would have echoed, as far as I was concerned, for all of eternity, and I found immense comfort from that ever since.
"Most months I come up here and walk and every time I pass it (the tree) I do feel comforted. I know it's where I'll go. It's still here and I'm still here, but it does speak of the importance of place and the joy of being connected with a place," before adding that one day he knows he will walk around the tree.
Sharing the video on Twitter, one doctor said it also explains why they talk to patients in a coma, referencing the link between Mindy shouting at Hammond and how that influenced his dream before he woke up.
"This is why we talk to our patients even when sedated" he said. "Why they get their hand held, hair sorted, music on. We look after people, not numbers."