We are on the island of Ometepe to climb a volcano. Though the kids are still small and the volcano is big, we have decided that it is one of those elemental experiences that we should go through at some point in our travels. Unknown to Matilda we have been training her up for just this moment. Those long cliff top walks, that 15,000 daily step target, the steep forest trails. We have chosen Volcán Maderas, the smaller and more dormant of the two volcanos on the island. It is going to be a ten hour round hike with an elevation of around 1400 meters.

When we awake on the big day we find ourselves enveloped in a blanket of cloud. It isn’t quite raining but it certainly isn’t dry either. Our guide Abel waits for us in reception. He is clearly a man of the mountain, slight, weatherbeaten, his eyes dark portals to another dimension.

Breakfast in the lodge comes slowly and perhaps we are not as organised as we should be, so we leave an hour later than planned. I sense Abel’s disapproval at the delays and the many rounds of pancakes we have eaten, but we laugh it off. By eight o clock we have shouldered our packs and we set off into the gloom.

The trails are overgrown and we are barely out of the gates when Abel already has to pull out his machete and hack a path through vines and shrubbery, much to Arthur’s delight. We march through a densely wooded valley and then up through coffee fields and abandoned cocoa plantations on the shoulder of the mountain. Then the climb starts to steepen.

There are various microclimates stacked at different altitudes up the mountain. All of them involve varying levels of moisture and low visibility. I imagine we are working our way up inside different cloud banks: first the nebulous mists of the low stratus layer, then into the dim white glow of cumulus. Higher up it is humid and dense as I imagine cumulonimbus to be. Then we hit a new kind of rain with a sharp wind that chills our sweat, and I figure we must have found cirrus, as this is the last kind of cloud I can remember.

The terrain underfoot changes from grass to dirt tracks and fallen leaves, to ferny vegetation, then mud, then rolling rocks and scree. For an hour Abel leads us up a stream in full flow, hopping stone to stone, splashing through muddy pools, crawling through rock tunnels, ducking under snatching branches. Matilda is the only member of the team who has proper hiking boots, the rest of us push on in wet trainers.

Abel turns out to be a guide in the minimalist sense: someone who is simply there to indicate the path to a destination. He is not a tour guide, we do not learn about the history of the island, the eco-system, local traditions. If anything he is like a silent spirit guide, floating in and out of the mist ahead of us, leading us along some metaphorical inward journey. He shows no signs of tiredness, he never stumbles. He slips away to scout the path ahead and some minutes later we round a corner to find him squatting immobile on a rock, face raised, communing silently with the ancestors. He pushes a fast pace.

I am using behavioural psychology tricks picked up over some years in sales management to motivate my poor daughter. We have anchored past successes (remember that time you climbed the cliff in Madeira with hardly a moan). We have engaged a sense of competition (and you got there before Arthur…). We’ve visualised the route ahead, we’ve established intrinsic motivators, we’ve set goals and we’ve quantified rewards (gummy bear every half hour, bar of chocolate at lunch, two puddings tonight). Now she is powering up the mountain, bouncing along chattering away to Abel who doesn’t say much back. She has found a ski pole in the lodge and she fiercely stabs it into the mud with every step. In fact it’s uber-fit Menna, who runs twenty five kilometres without fail every week, who is the first to start struggling. She is sliding around and lagging behind the group, sweating and frowning fiercely.

Arthur’s style of movement is not slow or steady. He jumps and bounces, slips and crashes, tries to make difficult jumps, falls a lot, wastes energy. He is always in danger of turning an ankle. He cycles through emotions from elation to dejection and offers a constant running commentary on his progress. He is the next to crash.

When it is my turn to hit the wall, it is intense. We’ve been climbing solidly for about three hours, I am wet through and I have a dull percussive ache in my quads which flares every time I have to lunge up another thigh-high rock. My backpack contains eight litres of water, it digs into my shoulders and catches on tree branches as we squeeze through gaps. My breath is short, my heart is hammering, my feet squelch. I am very glad when Abel calls a halt and I wolf down half a pack of peanuts and a secret handful of gummy bears.

We make summit just after one pm. There are no life-changing views or blinding moments of self-revelation, my spirit animal fails to materialise. Instead Abel indicates a point of cloud-covered rock like many others and tells us that this is the highest point. We nod and puff, then wind our way between various smokey outcroppings before sliding over the other side, through a series of steep and slippery faces, down into the crater.

An hour later we have reached our destination. We stand around uncertainly at the edge of the crater lake which stretches away into the mist like a grey shroud. A few stakes reach up ominously out of the water. Abel won’t confirm that they were used for ritualistic sacrifices, but one has an old skull on it, an oxen I think. We half-heartedly throw a in few stones, which land with muffled plunks and stir up some sullen ripples. We have literally no idea how large the crater is, how high the walls that surround us. How deep are the netherworlds that lie beneath that lifeless surface? We stand in a cold wet marshland with the silhouettes of mossy trees and bromeliads above us.

I was expecting Abel to light a fire at this point, start chanting and brew up the ayahuasca, but he just stands around wordlessly. It is too wet to sit so Menna and I crouch down and make sandwiches on a tree stump, then we all stand around in a circle stuffing in ham and cream cheese, chorizo, mango, oranges, chocolate. Abel doesn’t seem to have any food with him. No doubt he was intending to lunch on dew and wild berries, or perhaps just to chew on hallucinogenic tree bark. We feed him a sandwich or two, then he transmogrifies into a bat and flies away to the spirit world for ten minutes while we digest.

We haven’t managed to sit down at all, so our trembly tired legs are hardly rested when we have to shoulder our packs and turn back for home. Abel clearly thinks we have energy to spare so he takes us on a longer, more perilous route out of the crater that involves a long stretch of hand to hand climbing up a mudslide. We complain but he no longer hears us, he is tuned into the low rumblings of the volcano, drawing energy from magnetic fields deep beneath us. He floats across the slippery mud face, each touch gentle and tender. We lumber after him, stumbling, sliding, occasionally screaming, making a chain with our hands so none of us slip into the abyss.

Then we are over the summit and back into the cirrocumulus landscape. The return journey is not the gentle downhill ramble we had hoped for, but a slippery losing fight against gravity where each downward step places stiff demands upon tired knees, the falls multiply, the chatter dries up.

I have nothing much to say about those three nightmarish hours. Arthur spots an armadillo, Matilda doesn’t once moan and Abel himself slips over a couple of kilometres from home, which cheers us all up immensely and gives us the psychological boost we need to complete the trip.

The next morning we are greeted by the manager of our lodge in a state of high excitement. He tells us that as far as he is aware, Matilda is the youngest person ever to make it up to the crater lake and return alive.

He asks for a picture for the hotel notice board.