It may seem rather odd to go out cycling at half-past-one in the morning, but then I suppose I’m a rather odd kind of person. That’s what comes of wishing you were a horse for thirty years...

It had been a mistake to log onto the TSA tonight. Work had been hell, and I’d watched some gloomy documentary on television on a subject that didn’t interest me but had nevertheless depressed me. I should know better than to read stories about transforming into a horse when I’m in that kind of mood.

Oh, I love them! Don’t get me wrong on that, but when I’ve read them I’m left with an almost physically painful envy: a yearning to enter into that story and take part in it. And if I’m not feeling in a very good mood to begin with, well, bang goes any chance of a peaceful night’s sleep. I toss and turn, bemoan the fate that caused me to be born human, and end up completely miserable.

So, recognising the symptoms, I thought, "Not tonight!" Instead I went cycling.

At first I didn’t head in any particular direction, but soon decided I wanted to get clear of London suburbia. I wanted a bit of space around me and an absence -or at least a reduction- of human-crafted scenery around me. I turned south toward Epsom Downs.

Okay. If going cycling at this hour is crazy, cycling up to the top of the Downs (ironic name, don’t you think? I mean nowhere is more up than the Downs!) is probably certifiable. Whichever route you take, you end up having to cycle about a mile and a half of steep, upward gradient, on a road rough enough to rob you of any labour-saving momentum you might gain. Strong thighs and twenty-one gear bicycles only. Fortunately I have both.

The climb has its compensations though. When I eventually reached the crest of the downs, I had a phenomenal view of night-time London spread out beneath me: a huge web of orange street lights. From this detached viewpoint it was quite beautiful and not at all the dusty, ugly city I knew so much of it to be up close.

But the downs themselves are special at night. No streetlights there, and night has a firm hold of the land. The wind is never entirely still there, and thanks to the racecourse and it being quite a rich area, relatively undeveloped and wild. Or at least, usually it is. I’d forgotten the date: it was now June 7th. Derby Day. The normally vacant stretches of grass were now a mass of caravans and fair-ground booths. But it was till quiet: at this time of night, even Piccadily Circus is quiet.

As usual (yeah, I do this a lot) I stopped my bike and sat there, unmoving, feeling the cool wind wash over me; its lonely rushing the only sound to be heard. A quarter mile away, dimly lit, the huge modern grandstand crouched like a giant sentinel, commanding a view of miles. Closer at hand, far less grandiose, the Tattenham Corner pub nestled in a cosy pool of light from its own floods. Where I sat was in darkness: isolated, yet exposed. I felt the wind rushing in my hair and grinned into the night. At such times, it seemed like the world was mine.

I sighed and resumed pedaling, pausing again at the end of the racecourse. Some of the world's fastest horses would race each other across this spot in a few hours time. It seemed almost unbelievable seen like this: so remote: so desolate.

At this end of the five furlong straight, the main road bisects the course. When the racing requires it, the road is closed off and mats of synthetic turf laid across it. It was semi-prepared now, the removable fencing shoved aside so that I could stop and stare down the whole straight to the finishing line. I could just make out the outline of the course from starlight and a slender moon.

I grinned again, a little self-consciously this time. I wonder if any of you, some of whom I know share the same dream as I, can understand the urge I felt then? There was no one about; no one to see. A little harmless role-playing, and when I got home, a little boasting on the Internet: "I ran at Epsom today: it was Derby Day you see!"

I got off my bike, leaning it against the fence. The road was visible for a long way in both directions: there were no telltale beams from approaching cars. There were no caravans in the immediate vicinity

Just a short way, I thought. Fourth to third furlong markers. Enough to truthfully say "I've run at Epsom!"

The ground beneath my feet was invisible. Only by staring at the glow of the grandstand at the finishline could I see in my peripheral vision the line of the course in the moonlight. I took a deep breath and a final look around, and began to run. High-stepping, more like a trotter than a racehorse to avoid tripping on the unexpectedly rough grass, I jogged at an easy pace down the slight incline. I wasn't trying to sprint: I'm a good cyclist but a lousy runner, and anyway, what makes good running for a horse is not always good running for a human - even one who wishes he were a horse - and a faster pace would have had me tripping over clumps of grass in the dark.

Nevertheless, it was surprisingly easy to run, and when I passed the three furlong marker I kept going. I has happily recalling all the famous names that had galloped to victory down this famous stretch of turf since Diomed first won it in 1780, finding it impossible to believe I was following in their hoofprints: Gladiateur, Iroquois... Such were my thoughts when I twisted my ankle on a tussock and tripped...

...My balance shot, I almost careered into the horse beside me: I heard his rider shout something angrily: felt my own rider hurriedly shifting to maintain his balance. Ears back, I lost way for several strides, the rest of the field closing around me. All was thunder and flying divots: another horse's tail streamed across my face, and then my rider was hauling back on the reins. What was he doing? The way was forward! I neighed, fighting the bit that pulled hard at my mouth. Slowed despite myself, I dropped back out of the tail end of the field. Suddenly there was space about me.

The reins and my rider's subtly shifted weight urged me to one side, and I soon saw the sense of it: open way! I scarcely needed the urgings of my rider, the sting of the whip. My hind legs gouged clods of turf up and flung them high as I surged forward. I found my rythym again and began to steadily gain on the field. Peripherally, I was aware of crowds of humans to either side, lining the stretch of green down which I pounded.

I was passing the field now, and still accelerating. Adrenaline bore me along so that I felt I could run like this forever: head forward and low, tail streaming, legs a flashing blur.

Two horses remained in front of me, running almost as one. Then we were neck and neck, and I fought to gain yet more speed. It hurt, but I found it, just as we flashed past an especially dense crowd of humans. Little boxes they held to their faces blared light at us in a strobing crescendo, and suddenly, I sensed, the pressure was gone. My rider relaxed, and I recognised his hand on my neck. "Easy boy, easy. Good boy. Nice and easy now. Woah there. Good boy..." I snorted, pleased, arching my neck and slowly reducing my pace down to an easy canter. A tinny human voice was echoing in the air: "...outsider Sudden Change takes this year's Vodaphone Derby against all odds! Photo second Billy the Dip and Silver Patriarch. Fouth Romanov, and the favourite Entrepaneur comes in fifth place..." The words meant little to me, but I recognised my name amongst them. I snorted again, slowing to a walk...

...And stopping dead, looking around me in astonishment. The sunlight, the sound of the human crowds and other horses around me faded into smoky dreams leaving me dazed and confused. Quiet night sounds surrounded me, and to my right the imposing terraces of the grandstand... too close and too well lit for comfort. Someone might see me here! I turned, walking to the far rail and following it back up the course. My legs ached fiercely.

What had happened? Anything? Just a dream brought on by my too-eager imagination? I couldn't tell: already I was just left with the memory of a memory. The immediacy of the experience was gone as abruptly as it had come. Shaking my head, I made my way back to my bike, and then home. I didn't log onto the Internet as planned but instead went straight to bed, troubled and confused, cursing myself for a fool at having thought a bike ride would cure anything.

But I woke refreshed, happy to dismiss last night's experience as a dream. I struggled to my feet, shaking sawdust from my coat, stretching my head out over the door and neighing in anticipation of the morning feed. A voice, faintly echoing in my mind like a comfortable memory, said, "I ran at Epsom today: it was Derby Day you see...." The words meant nothing to me but there was a smug air of quiet accomplishment about them.

I blow through my nostrils, snorting. Where is that food?