I spend a sleepless night wondering if I have been incredibly stupid handing over $300 to a stranger that I've met in the street. Next morning to my relief and surprise it seems like it is "game on" as I am introduced to a safari/trekking company and we set off to conquer Mount Meru.

The mountain is relatively high and has 4 separate environments depending on altitude. There are evergreen forests, floral meadows, giant lobelia and alpine desert. There are five in our party, me (obviously) Deo (chef) Enock (guide) Frederick (ranger) and an elderly porter who doesn't say a great deal. I am the only punter on our trip so things might get lonely on the mountain. Frederick is a ranger with the Arusha National Park (you aren't allowed to climb the mountain without one) and is the one that I walk with most as he has the gun (to scare off any wild buffalo) and he is effectively the guide.

The climb is scheduled for three days and many people have told me that Meru is harder than Kili because of the shorter time to climb (no acclimatization here!) and the steepness of Meru. When I've done Kili (don't know when!) I will update you. The climb is very deceptive because the first two days are like a nature trial. We spend 3-4 hours climbing around 1000m each day and I feel absolutely fine at the end of day 2 when we reach Saddle Hut at 3570m, so much so that Enock and I climb Little Meru Peak (3820m) for something to do in the afternoon. We are the only group ascending at this point and it is a little spooky being the only group on the mountain staying at Saddle Hut.

Accommodation on the mountain is very basic and consists of wooden huts which do little to stop the cold. At least we aren't camping! No running water at these heights either, never mind hot water.

The final day of the ascent to the summit is a whole different ballgame. It's 1.40am when, after a brief breakfast, Frederick (minus gun - no wild buffalo at this altitude) and I set off on our own. I have two torches. which prove to be superfluous because there is enough natural light from the full moon to light up our path. The temperature is freezing (Deo gave me a hot water bottle on the previous evening!) but we are moving fast and this seems to ward off the cold. The ascent takes us (well me, Frederick is like a mountain antelope) 4 hours 30 minutes, the mountain is steep and the ground underneath varies from rocks that we have to scramble over on all fours to soft volcanic ash which was probably worse as it was like trying to walk up a very steep sandbank. I am continually sliding backwards and losing my footing. As we approach the summit we encounter snow, just to make the last metres of the climb even more dangerous. Several times I find myself questioning my sanity in attempting this, each time I take a sip of cool water and march onwards. Eventually my single-mindedness is rewarded as, exhausted and wheezing, we reach the summit just as the day is breaking around us. The sense of achievement at having successfully reached the summit was great.

The temperature at the top of the mountain is subzero and standing still was a poor option. I quickly took some photographs and having spent no more than 10 minutes at the summit we begin our descent. I am full of beans on the way down, in sharp contrast to the crawling mess I was about 20 minutes earlier. Now it is light I can see the spectacular landscape that is the mountain itself. Meru was a volcano that exploded and destroyed much of itself. There is still as ash cone inside the mountain and the area looks like something from pre-historic times. After getting back to Saddle Hut we descend to the bottom of the mountain, in total I have walked for 11 hours.

This was quite simply the hardest physical challenge that I have ever undertaken. It was also mentally very challenging as there was no group of people there to lend support during the dark moments. The sense of achievement at the end of it was immense and it was certainly worthwhile, especially as I am writing this from the rooftop terrace of my hostel which looks out directly at the mountain.