Mali conflict: Desert fighting on 'Mars'
French-led forces have recovered the main cities in northern Mali held by Islamist rebels. But in the desert, the fighting goes on, in terrain that appears to be from another planet.
The helicopter flew with its lights off in the dead of night.
When we finally landed, we could feel the sharp rocks under our boots but still could not see anything. It felt like we were cut off from the rest of the world.
Later the first light of dawn revealed the vastness of a rocky desert, with mountain crests and sandy lines cutting through the landscape like human veins. I don't think I have ever felt that small, that insignificant.
As the sun rose, soldiers appeared one after another in their beige uniforms, ready to march through yet another day in this hostile wilderness.
These men were from the French Foreign Legion, a force which, uniquely, draws its soldiers from many nationalities.
Traditionally it is prepared to draw a veil over a candidate's background or criminal record.
But today many Eastern Europeans or South Americans join up simply because they can earn a lot more money than they would with their own countries' armies.
"We've just left planet Earth and we're now on Mars," a Romanian legionnaire shouted.
We were climbing a steep hill, over jagged and slippery rocks, at the time.
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From the top we hoped to get a view of the whole valley below.
With flak jacket on, helmet, rucksack, TV and radio equipment, enough food for the day and six litres of water, we were carrying more than 30 kilos in weight.
The soldiers, with their weapons and ammunition, each carried twice that weight.
By 9am, we had been walking for three hours and it was over 40 degrees Celsius.
The heat waves were actually visible in the air, and as an Australian corporal put it to me: "A bit of wind feels like someone aiming a blow-dryer right into your face."
The legionnaires were searching the desert for jihadi fighters. They had discovered plenty of their hideouts already.
In some, established near the rare wells in this dry and arid landscape, militants had grown their own vegetable gardens.
The soldiers loved the fresh tomatoes and onions - delicacies after days of military rations.
One legionnaire pointed towards his boots - they were so destroyed by the rocks that he was happy to find a pair which had been abandoned by the enemy.
He swapped his boots and joked about wearing "jihadi shoes".
Most of the soldiers had served in Afghanistan. One said that the trickiest thing there was that as soon as they engaged the enemy, they would melt away into the villages.
Here, though, they can be anywhere around us. And they fight to the death.
We did not run into a firefight during the two days we spent marching with the Legion.
But we found explosives and other items left behind by the jihadis.
We had seen the remains of suicide bombers in the northern town of Gao. Now we were looking at the sort of explosive belts they used.
A French de-mining engineer explained that they were very sophisticated with detonators made of copper, which is harder for metal detectors to spot.
There were also drums filled with nitrate for making bombs. The French blew them all up before we moved on.
We entered a dry sandy riverbed, which led to a long stretch of flat desert.
We had to reach a hill on the far side and the officer in charge, Captain Clement, was worried we would be too exposed, out in the open: "We won't be able to take cover if anything happens."
But there was no other way. We had to do it in one go, and fast.
As we started to sprint, the captain explained that one of his men had been shot and wounded by a sniper a few weeks before.
Eventually we reached the top of the hill on the far side of that flat stretch of desert. We all fell to the ground.
The rocks we lay on felt like burning coals but we were so exhausted, standing up was simply not an option.
My mouth and throat were dry. It was painful to swallow.
We marched nearly all that day under the boiling sun. When darkness eventually fell, the temperature, in this landscape of extremes, rapidly dropped to freezing point.
Exhausted, we lay our sleeping bags on the desert floor, climbed in and went to sleep under the stars.
The legionnaires had been chasing jihadi fighters on foot for weeks. They had lost track of time.
For them, this was just another day in Mali's far north or, as they call it, planet Mars.
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