Part of the Sahara A to Z series

Out in Niger’s Tenere desert, east of the Aïr mountains lies the isolated massif of Adrar Madet.
About 2.5 kilometres directly west of the 20-km long massif’s northern tip, a perfect stone circle lies in the sand.
The circle is about 20m in diametre and some 600m from the circle and more or less at each cardinal point is a small arrow. You can see all five points here on Bing. You won’t see them on Google.

I’ve not been there but have known about it for years. Some speculate that it could a sacred pre-historic marker associated with prime meridians and ancient Egyptian knowledge, marking the ‘middle of North Africa’ (left).
It is a huge coincidence that the circle is – within a few kilometres – exactly halfway between the equator and Ras Angela near Bizerte in Tunisia, the northernmost point of Africa. And it’s nearly directly south (178.4°) of Ras Angela, too. (Fwiw, it’s 64km west to the actual point directly south of Ras Angela, just south of Arakao on the edge of the Aïr.)

I err more towards the idea of a much less ancient aviation landmark from the colonial era, one of many located in the Sahara and still being found, including less ambiguous examples where names of nearby outposts are stencilled inside the circles. Fellow Saharaholic, Yves Rohmer confirms this fact. Rubbish from that era: tin cans, bottles of Pastis and so on, littered the Madet site. A similar circle exists in nearby Fachi, with that name stencilled in it and close to an old airstrip. Another plausible explanation made in the discussion linked above was a drop zone for parachute or dummy bomb training.

Not so mysterious after all then, but you do wonder, with the distinctive and isolated 20-km-long Madet ridge angled NW/SE and the Aïr massif to the west, what value the tiny 20-m stone compass actually added to aerial navigation? And why put an airstrip there if anywhere flat in the Sahara can be an ’emergency airstrip’. And would they have spent days building a parachute or bomb drop zone circle when a ring of smoking oil drums would have sufficed?

Another possibility I like to entertain is of a playful or geographically inclined Colonel stationed in the Sahara. He’d spent his lovelorn honeymoon in Bizerte and, looking at his Michelin map one hot day, noticed Adrar Madet’s central position. He decided it would be a good morale-building (or time-killing) exercise to have the circle and cardinal points marked in the desert for posterity. But as Adrar Madet is far from any route or useful resource, the purpose and meaning of his enigmatic earth sculpture has been lost in the sands of time.

That’s as may be, but what about the other similar but smaller cobbled stone circles I’ve seen in the mountains of southern Algeria (below)? Neither could be described as aviation markers. ‘Tombs’ said the guides, but they’re not like the usual pre-Islamic tombs of the desert.

Timetrine, Mali

Here’s another curious circle, spotted by a mate in the remote wastes of Timetrine, northern Mali, coincidentally one place where AQIM kept European kidnap hostages up to a few years ago.

19.455065, -0.422889; It’s a lot clearer on Bing Maps than Google. According to the old 200k IGN map, this is actually the brackish (saumâtre) well of T-in Kar (wrongly positioned on Bing), so marking it for pilots may make sense for emergencies.

You will see four points a couple of hundred metres from the circle set in the middle of a distinctively rectangular clay pan covering about half a square kilometre. But they seem so vaguely positioned as to be pointless. Some have speculated the four points may mark the fringes of a smooth landing strip.

The clay pan is on a more-or-less direct line between Timbuktu and Tessalit where there is also a ‘TES’ marker by the current airfield (left). In those days (pre-War) they would have navigated as much by landmarks as a bearing.
Since around 2013 this whole area has been a war zone between mostly French forces under Operation Barkhane, having it out with AQIM and the like. So far this intervention has been as successful as similar operations in Iraq and Afghanistan and by 2023 they’d left.