It’s 4 a.m., and I’m wide awake, coming round with a start in a hot motel in Mariposa, my first thought is “She did it!”

Ella, my 13-year-old daughter, is sleeping in the bed next to me like only a teenager could sleep, so deep only an earthquake could break it, and she deserves it; last night she was sleeping on El Cap, having climbed Tangerine Trip over four hard days and nights. If there’s any teenager on the planet who deserves to sleep in today, it’s Ella.

I’m sure for everyone who thinks it’s amazing that someone so young could find the strength to climb El Cap, there will be those that will be appalled that a father would risk his child’s life in such a way. To be honest, I find myself seeing it from both sides, and this adventure has been one of considerable soul searching and stress, as well as laughter and moments that made me want to cry with joy.

I guess I should start at the beginning.

For many years I’ve brought my kids Ella and Ewen along to my slideshows, as well as events like the Kendal Mountain Film festival. They’ve sat through dozens of talks, sometimes even laying on the stage at my feet, chuckling away. At first, I felt a bit uneasy, after all, do I want my kids listening to all these tales of daring do? But climbing and the rewards and risks of that life make me who I am, and the lessons it has taught me are lessons I’ve tried to pass on to my kids. Adventure is in my DNA, and so it’s in theirs also, and so they should see what I get up to when I’m away, and understand both the risks and rewards of striving for impossible things.

I’ve never been a pushy climbing parent and always wanted to leave it up to them to decide how to explore the boundaries of themselves, exposing them to wilderness and danger the way my dad did, giving the impression of both while keeping them on a short leash.

One question that kept coming up at talks was “When are you going to climb El Cap with your kids?” to which I’d reply “Oh not until Ella’s 13”, thinking the youngest girl to climb El Cap was that age (turns out she was 14!). This always got a laugh, mainly because it was obviously a crazy idea. Then Ella turned 13, and she asked the question “so dad, when are we going to climb El Cap?”.

My first reaction was “Why not?” Having climbed it nearly twenty times (soloed it three times, climbed it in 18 hours, spent 11 days doing its hardest route, and almost two months hanging from it), I thought I knew enough to keep her safe. Also having climbed it with two people with disabilities (Karen Darke and Phil Packer) I also understood just what was possible. When you’ve seen a woman do four thousand pull ups, and use only her arms (and nerve) to climb El Cap, you know it would be easier for a 13-year-old - well physically at least.

And so I said “maybe we’ll go in the spring holidays next year” having no real plans to plan on doing so.

But Ella is persistent, and now when we went climbing she would want to learn how to jumar, how to abseil, ask me how she would go to the toilet ‘when we’ (not ‘if we’) climbed El Cap.

Very soon her mum (my long suffering ex-wife) said “What’s this about Ella climbing El Cap?”, to which I replied, “oh it’s just a phase - she’ll soon forget about it”, thinking at 13 she’d soon be thinking more about boys than big walls.

But like most adults, I underestimated my child.

She had made it her goal to climb El Cap, and I realised to let her down was something I couldn’t do. I had to make it happen, no matter what it took.

The first person to be convinced was Mandy, Ella’s mum. I left this up to Ella to negotiate, knowing full well the persistence of a child is the greatest force in nature to change adult minds! The answer was a yes - but only on the conditions she would be safe, and that my mate Paul Tattersall was there - the only climber Mandy trusted. Paul agreed to come if I could cover the cost of the trip and so with much reluctance Mandy gave Ella her blessing.

In life, if you set out with the purpose of doing something amazing you invariably find that circumstance will lend a hand (I’ve always lived by that motto “Act boldly and unseen forces will come to your aid”). The first thing was a talented film maker called Ian Burton got in touch with an idea for a TV program about climbing El Cap with an ex Royal Marine sniper named Aldo Kane, seeing how someone like that (a trained killer!) would get on on a wall. “How about we took Ella along as well?” I suggested, and so the idea was born. Better still Ian could cover all the costs of the trip (I had yet to work out how to pay for me, Ella and Paul to climb El Cap).

A date set, we started to train with more focus, Ella learning how to pass knots, wall safety, aiding, self-rescue, cleaning pitches. She would have to miss some school and permission was granted (now that’s what I call a progressive school!). The months turned to weeks and then days before we were due to go.

And then it all fell apart. Ian could not get a visa to enter the US. With no money to pay for the trip, it fell through.

As you can imagine, although she put on a brave face, I knew Ella was deeply disappointed.

I guess before then I’d just been going along with the notion of climbing El Cap with her, but now I knew it was more than just a climb, it was stepping up and fighting to make it happen, no matter what.

We’d had a plan to climb as a five person team, with Paul leading, Aldo cleaning (who I’d yet to meet, but knew as a safety rigger - and trained killer - he would be invaluable on the wall), me hauling, Ella jugging and Ian filming. The technique was the same as a Russian four person big wall system (2 pushing up ropes, two hauling up kit behind), which although heavy was very safe.

Telling Ella that we’d not be going was hard, and harder when she said that Mandy had said I’d probably not do it anyway, “well dad you are a bit unreliable”. That was it; this was no longer about Ella climbing El Cap, it was about a father fulfilling a promise (I only wish it had just been buying her a bloody horse!).

Again forces came to my aid. Aldo was happy to pay his way there, glad just to be invited to climb a big wall, while a cheque arrived for my first royalties for Cold Wars. The money cashed, I spent the lot on two tickets to San Fransisco, showing the confirmation to Ella.

We were going!

And so two weeks ago we finally reached Yosemite, arriving at night, Ella’s first impression of El Cap being its bulk blocking out the stars, the border between wall and space blurred by the pinpricks of head torches high on the Nose.

We were unable to climb until 5.30am on the following Monday morning due to our filming permit, so hung around the valley doing very little due to the heat, the coolness of autumn still absent. In fact, I’d never felt such heat in Yosemite, even in June, the temperature up in the 90s. I began to wonder if it would be possible to even climb in such heat, as beyond the Nose the wall was almost empty (apart from Brits Vick and Guy climbing Zodiac, and Brit Ollie soloing Tangerine Trip, all proving the adage about ‘Mad dogs and Englishmen”).

Paul and Aldo and I took turns fixing ropes up to pitch five on Tangerine Trip, a route I’d climbed in winter conditions with Matt Dickinson many years before, and chosen due to its steepness (steepest route on El Cap), meaning it would be safe in a storm and secure to jug. The heat was brutal, as just climbing one pitch left both climbers close to heat stroke.

I began to have doubts about the feasibility of climbing the wall, while at the same time Ella was chomping at the bit. She had started to immerse herself in the Valley, its strange collection of people, its names and rules, bus circuits and cafeteria menus. One day I said “maybe if we finish early we could go to San Francisco and visit Alcatraz, to which she replied “can’t we climb Lost Arrow Spire instead?”

Eventually, Sunday came around, and I knew we just had to make it work, carrying 90 litres of water up the base (we planned on three hanging bivis) the night before. We set up in the dark to bivy at the base, dodging two rattlesnakes who were laid out on the rocks enjoying the slow release of heat from the heat locking in the talus.

Oh, how I wished I’d been cold blooded in the days that followed.

As usual on a big wall with such a big team, day one was a disaster. We all jugged a free hanging rope for about 100 metres; then I began hauling while Paul and Aldo pushed out the ropes. The weight of the haul bags (99 litres of water, four days food for 5, three ledges, plus assorted crap) was insane. I, Ella and Ben were on the belay all day as I inched the haul bags up while being roasted in the sun.

I spent most of the first day either hauling or telling Ella to drink, paranoid about her getting heat stroke. Finally, the bags arrived, but so did the night, meaning we bivvied where we’d been all day, only hoping tomorrow would be better. The only consolation was Ella had overcome her 2nd biggest hurdle: weeing on the wall, which although messy for me (she weed on my legs and boots), was quick and efficient.

The following day was better but still slow and marked by more heat and some massive lower outs for me, Ella and Ben. In the morning Ella had conquered her 1st biggest fear by having a crap in a wag bag (hanging her bum over the edge with the wag bag clasped around her), so I felt things were looking up. My biggest worry was the amount of water we were drinking. Again Aldo and Paul pushed the ropes up, and we followed.

On each pitch Ella had to jumar a fixed rope (backed up by a shunt on the haul line), inching her way up on her jumars. As each pitch progressed, she got more and more tired, getting slower and slower. A few people had asked what I’d do if she couldn’t get up the wall and my reply was “well she’ll have to!” - never actually considering what if she couldn’t.

That night, like the rest of the team, she was so tired I had to take her shoes off, and get her in her sleeping bag, seeing in her the heavy fatigue that only a wall can bring.

The following morning we were only halfway up the wall, and it was tough getting her started, but started she had to be, as we had to move as quickly as possible to get to the top before we ran out of water. The sun had become something dreadful, like something out of a science fiction film, drawing near at dawn, and bearing down all day until finally losing its grip just before dark. Worse still El Cap was devoid of its usual winds that cool you down, and again and again, I kept getting that T. E. Lawrence line in my head “In the desert there is nothing, and no man needs nothing”.

On this third day, Ella needed to be cajoled, bullied and distracted up the rope, her fatigue visible. Having done many walks, climbs and paddles with the kids, I had a lot of experiences of this, but now this was serious, as I found my fatigue hauling the bags too much to deal with. The low point came when I lowered Ella off a belay, and she realised she’d dropped her iPod, a gift from her mum and engraved with her name. She started to cry and just hung on the rope at the end of her tether. I shouted up to Ben and Aldo that they should be prepared to haul Ella up the next two pitches, as she was too tired to do it, and in an instant, she came round and shouted “No! I want to do it myself - if I don’t I’ll only be disappointed”, and with that, she slowly made her way up two more rope lengths to the belay. To say I was stunned by her strength, grit and determination would be an understatement. I knew it was this show of will that I had wanted to mine all along, the inner strength that she had (and we all have), but even so, I had to find my strength not to cry.

That night Ella fully endorsed the dirt bag life of a wall climber, drinking a can of Pepsi, eating a tin of pineapple, tuna mixed with soft cheese and a tin of cold beans and sausages. I asked her what stopped her crying and she said “I just thought that my iPod would always be in this beautiful place and that was ok… Plus you said you’d buy me an iPad” (I’d forgotten that bit!).

The last day on the wall was amazing as finally the sun lost its grip and the wind came, cooling us off as we climbed the last three pitches. Big walls are always like this. They grip you so tight you feel as if they will kill you and you’ll never reach the top, and then, at the moment you relax, finally understand its lesson, it releases its grip.

On the final pitch, Ella wanted to free climb, so I belayed her up, easy climbing for her in her trainers, but still on the edge of the world.

As is always the case, there was no room for celebrations as haul bags got pulled up one by one, and kit sorted. Each team member coming up one by one (what a great team this was - a band of brothers - and a little sister). As I pulled up the last bag Aldo pointed away from the edge and I saw Ella sat crossed legs in the dirt, her head bowed forward resting on a tin of beans and sausages, fast asleep.

As with all such climbs, there is much to unpack afterwards - both physically and emotionally, so much it can take a lifetime. To spend two weeks alone with Ella was fantastic, and also startling, enlightening and surprising. I saw this little girl grow before my eyes into someone amazing. It was also sad, as I knew she hadn’t become this person on the wall, but in the 13 years it took to get there. Before me was this human being who could get rigged up to jumars herself, carry a big pack, and remain upbeat at the lowest moments, someone who thought her thoughts and could look after herself. She tied on as my baby and untied as an equal to us all.

One thing I was always scared about was that it might all go to her head. But when we boarded the shuttle bus yesterday afternoon, the five of us looking so battered, and I said, “This 13-year-old girl just climbed El Cap”, and the whole bus clapped her, I could see only an embarrassed pride.