Great Sand Dunes National Monument, CO

It seemed like such a good idea at the time. Like doing a Masters, for instance, or eating a Lamb Madras at lunchtime. It was a beautiful morning, the sun was out, we had a couple of hours to kill, what better time to take a casual stroll up a hill?

I'm in the Great Sand Dunes National Monument - halfway up what is quite possibly the largest dune on the planet - in a state of considerable distress. The sun is beating down hard on my back and my lungs are struggling to take in enough thin alpine air. We're at 8,000 feet above sea level today, and it feels like 80,000. The sand is so soft that every forward step takes me halfway back to where I was the step before. It's a 230 metre high dune but it might as well be a 460 metre climb. And with every ridge I negotiate, there is another view of the summit of the dune getting further and further out of reach.

"Allow 2 hours return for Star Dune summit walk", read the sign in the carpark. Fine, fine, I thought, that's two hours for your run-of-the-mill sedentary beer-bellied American, and half an hour for me. Alarmingly though, there are no Americans fitting this description to be seen on this climb. The only other hikers I've seen are fit, supple and painfully enthusiastic. So this is where they keep the skinny ones! They're all roaming the sand dunes of Southern Colorado. Maybe they're actually in training in case America happens to get involved in some sort of armed conflict in a country with a predominantly desert landscape. The only fat Americans I've seen today were the cheerful family of seven in Boston Red Sox caps who I breezed past at the base of the dune. They didn't look like making it up the first hill, if I'm honest.

I can see Joey pulling further away from me up ahead. He has taken his shoes off and is making good progress. I have decided to keep mine on, mainly because of the bet I made with him before we started that wearing them would be an advantage, and I'm not going to give him the satisfaction of being right. My shoes are filled with sand and feel like lead weights now, making my chances of reaching the summit look ever slimmer. On the other hand, my chances of death are improving by the minute. I'm even beginning to picture the write-up in the local paper.

Police confirmed today that the badly decomposed body found in the Great Sand Dunes National Monument belongs to a New Zealand tourist missing since last June.

Authorities say the grisly discovery serves as a timely reminder that the dunes are not suitable for unfit, overweight, alcoholic hikers.

Around 20,000 New Zealanders visit the U.S. each year. A small island off the East coast of Australia, New Zealand is known for its formidable soccer team, the "All Blacks", who attempt to intimidate their opposition by performing a native wardance known as the hokey pokey.

The beauty of the sand dunes is that there are no paths to the summit, allowing you to pick and choose your own route. The unfortunate part is that I seem to have chosen the wrong route at almost every turn, making my journey twice as long as it needs to be. Somehow people walking twice as slowly as I am are ascending faster. I don't think I've got much left in me now, I think to myself, as I enter what appears to be the self-pity stage. It won't be long now before I find a nice peaceful hollow out of the wind, drink the last of my water, pull out my notebook and begin writing.

"Dear mother..."

"But dad, we didn't get to go to Dairy Queen yesterday, either!", comes a voice from the other side of the ridge. Unbelievable! The family of seven in the Boston Red Sox caps are still making their way up the dune and within seconds will be pulling level with me. I may be most of the way to death, but there are some indignities that I would never be able to live with. Drawing upon the last of my strength, I struggle to my feet, grit my teeth, cast a pose, grit my teeth a bit more while I make entirely sure that I've got my breath, and push on towards the summit.

As I reach the top of the next ridge, Joey comes into sight once again. This time he is no longer moving. He must be at the summit! With renewed vigour I trudge ever upward, feet sinking half a metre into the sand with every step. I dare not even look up anymore. And then suddenly, I arrive at a point where there is nothing left to climb. In every direction, the sand drops off to smaller, lower dunes. I am at the summit. I am Hillary, atop my own 230m Everest.

And then the most remarkable thing of all happens. One by one, the Red Sox family arrives alongside me at the summit and collapse in varying states of mental and physical disrepair. We exchange smiles that speak of shared adversity. "Apparently it's a bit easier going back down", I say, airing a joke that has almost certainly never been heard in this situation before.

Needless to say, the views from up here are quite startling. To the west of the dunes, endless featureless plains stretch to the horizon. To the east rise the 14,000-foot peaks of the Sangre de Cristo Mountains (which at a wild guess translates as "Blood of Christ"). Behind me, on the route I have taken up the dune, tiny figures are milling about in the carpark and kids are playing in the nearby river. It would be a magnificently serene spot, except for the savage wind that is threatening to blow me back in the direction of Los Angeles at any moment.

Turns out the trip back down is a whole lot easier. Most of it involves sprinting down the face of slopes that I had been crawling up merely half an hour ago. At the base of the dunes, we cool our feet in the river and turn around to look at the Star Dune in all its monstrous splendour. Dozens of foolhardy climbers are making their way up in the midday sun, like ants on a giant anthill. Climbing sand dunes is so old, I decide. Been there, done that.