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.
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.
"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. 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".
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.