Technology has a remarkable way of spawning dubious hobbies. Aeroplanes and binoculars produced plane-spotting. Elastic led to bungee-jumping. And now GPS (Global Positioning System) devices, digital cameras and the internet have combined in a heady brew to bring about ... confluence- hunting.

It’s fairly easy to explain what it is. You visit a confluence — a point on the earth where lines of latitude and longitude meet — take a photo, and upload it to the Degree Confluence Project website. (Only the integer degree intersections, of course. Otherwise it would be ridiculous.) And it’s not hard to understand how it’s done. As measures, latitude and longitude have been around for centuries, but GPS devices have made it possible to know your position with absolute precision, and they’re cheap. Technology that, just a few years ago, was available only to Nasa and MI5 is now used as a stocking filler for small boys. Many new cars have a GPS built in, to provide reassurance when driving in Milton Keynes.

No, the tricky one is ... why? Why travel to a spot on the earth distinguished only by a mathematical accident? A good question. And there was only one way to find the answer.

ON THE morning of December 31, 2003, I leave Markoy, a small town in the far north of Burkina Faso, to go in search of fifteen zero, the confluence point where the line of latitude 15° North meets longitude 0° (the Greenwich meridian). According to the map, this point is in the desert in the south of Mali, 40km north of Markoy, and there is a track that goes within 10km of it. How hard can that be? My companions are an American missionary, Chris Ladish, and his teenage children. Chris and his family have lived in Burkina Faso for many years and so are used to difficult terrain. They are no strangers to confluencing, either; this will be the third notch on their GPS.

We follow the track north from Markoy, the level sands on each side punctuated only by pitiful acacia trees. Through the heat haze, a line of small hills on the horizon marks our eldorado; somewhere over there lies fifteen zero, just begging to be stepped on. We pass a line of blue-robed Bella women on donkeys, bearing goatskins full of water. We pass woven domes deserted by their nomadic Tuareg occupants at the end of the rainy season. We pass a hoopoe standing by the roadside, a glorious bird even to an orno-sceptic like myself. And all the while the GPS is winking at us — 25, 17, 11 kilometres to go.

The Confluence Project was started by Alex Jarrett back in 1996. “I liked the idea of visiting a location represented by a round number,” he says. “I also hoped to encourage people to get outside, tromp around in places they normally would never go, and take pictures.”

Jarrett points out that: “There is a confluence within 79km of you if you are on the surface of earth.” Who knows, there could be one in your kitchen.

There is no sign or boundary stone to mark our passage into Mali, probably because there is nothing here for a nation to be possessive about. We have gone as far as is helpful on the track and must tackle the last 10km cross-country. Progress is slow because of crevasses in the ground and stumpy, recently harvested millet fields.

“Oh no, it’s a wadi!” exclaims Chris, and I look up from the GPS, half expecting to see the slavering jaws of some fearsome Saharan monster.

But all I see is a dry river bed with sand in the bottom.

When we plough down into it, though, I see the reason for their dismay. In the deep sand, the vehicle’s movement immediately becomes sluggish. As it creeps towards the far bank, the engine screams its resistance, and several times we nearly stop. At last, the tyres bite on solid ground; we accel-erate up the bank and lurch over the top.

“That was close,” I say. Chris nods, then glances down. “Oops,” he says, and takes the handbrake off.

One kilometre from our goal we come to another wadi, this time deep and clearly impassable. We have to leave the truck behind and continue on foot: we walk as one, huddled around the precious GPS like schoolgirls around a mobile phone.

After 10 minutes or so we hit our line of latitude, 15°00’00”N. We stop, turn left and walk forwards again. 0°00’09”E, 0°00’08”E. “This is where the GPS batteries run out,” says Chris, and we laugh nervously.

With cat-like tread, upon our prey we steal. 0°00’03”E, 0°00’02”E. 0°00’01”E. We hold our breath. 0°00’00”E.

15°00’00”N, 0°00’00”E. We are there. There is a long silence while we gaze at the GPS. The sight of all those zeros makes me feel pleasantly giddy. Then someone cheers and the spell is broken. “Well done, well done,” we say to each other. Back-slapping would seem over the top, but a few firm handshakes are offered around. Welcome to fifteen zero, Mali’s second deflowered confluence.

FOR THE record, fifteen zero is in the middle of a vast expanse of loose rock and drifting sand. There is a line of small hills to the south, but in every other direction the desert stretches away to a flat horizon. We take photos obsessively, as if sheer volume of images can make this an interesting place. In many of these snapshots, the GPS is held close- up in the foreground, and we are desperately hoping that the midday sun will not erase those beautiful, liquid-crystal zeros from the photos. These pictures are the story and they need to be in cyberspace next week. Without them, our fellow adventurers at Confluence.org will not know that we have been here.

Chris’s son Marc reaches into his bag with a “look what I’ve got” expression on his face, and takes out a firework the size of a lollipop. He sticks it in fifteen zero and lights the wick. We withdraw, chuckling.

The rocket is a dud. It emits a small puff of smoke and flops sideways, and at that moment cynicism bites me. What we have achieved is futile. Latitude and longitude are convenient measures, but their integer intersections are basically meaningless. We have travelled to a non-place and confirmed for posterity that there is nothing interesting here. Oh, well, I am thinking, at least we saw that hoopoe on the way.

Back in Markoy, we are met by Roosman, an old Tuareg man resplendent in his white robes and indigo turban. He watches us appraisingly as we step out of the vehicle, covered from head to toe in red-grey dust.

“Toy njaadon?” he asks, frowning. Where have you been? I want to seize the old man by his beard and cackle and say, “We’ve been to fifteen zero.” But that would require an explanation as long as the Ancient Mariner’s.

“Fay nokku,” I hear myself say. Nowhere, really.

The Degree Confluence Project
www.confluence.org

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