After a couple of hours of rest, we headed out into the desert on a private vehicle driven by a railroad engineer who worked on repairing the railroad tracks for the SNIM company. Repair work consisted of removing old rusty sleepers and replacing them with new wooden ones as well as keeping the tracks in shape. The repair work is done on a moving basis with a 2km stretch being worked on at any point in time. It had to be planned carefully to avoid disruption to the movement of the trains. It just so happened that the tracks near Ben Amera were the ones currently being repaired, so the repair engineer and crew had taken up temporary residence on-site.
 
The engineer (Said was his name) drove us some 20 km across the desert on an overcast day with a cloak of sand seemingly hanging over us . Through the gloom we could see the endless desert dotted with small and large monolithic rocks. The largest of these is Ben Amera (which gives the region its name) which is the largest monolithic rock in Africa. According to some sources it is the second largest in the world, only Uluru in Australia is larger.
  
Said narrated the legend of Ben Amera and Ayesha, another monolith nearby that resembles a recumbent female form. Ben Amera banishes Ayesha after he learns of her being courted by a rival. She then settled close by along with her servants and slaves. Anyway that is what we understood after the multi-step translation that the story went through. Said narrated the story in Hassaniya, which was translated by S into German, and F translated it into English for our benefit. The world is full of rock formations that resemble the female form (The Grand Tetons in Wyoming, Iztazzihuatl near Mexico City come to mind) and this was yet another to be added to the list. Another curiosity near Ben Amera was the presence of a "rock art gallery" in the desert featuring contemporary work .

Video of driving through the desert to see the Ben Amera monolith
 
On our return that afternoon, we were introduced to the Mauritanian tea culture in the house of a family in the village. There seemed to be several generations in the room and it was not clear if they all belonged to the same family, but that did not matter. The eldest male was having his beard trimmed by a young man while another middle-aged man was in charge of making tea. The ritual involves tea being served in three courses. Our guidebook said it was ok to decline after the third helping. The green tea is of Chinese origin but is sweetened with a generous helping of sugar (no Chinese would ever do that!). The preparation is elaborate with much pouring between the kettle and the various cups using a high arm action which brings forth a lot of froth. Each offering is just a mouthful but a very satisfying one. 

Ben Amera village is essentially a cluster of few mud houses and a few 'boutiques' (small shop selling essentials) . There are no restaurants and we were left to our own devices to take care of dinner. Fortunately the family that had invited us earlier for tea, offered the use of their kitchen to prepare something ourselves. S and F, resourceful as ever, came back from a quick shopping trip with ingredients needed for a quick pasta dinner. We went to work cutting vegetables and boiling pasta in a barely lit kitchen squatting in in front of a low stove. The results were not bad.

S made inquiries on the options available to get to Choum the next day. Hiring a 4x4 to Choum would be too expensive as the vehicle would have to come from Choum and return. After much discussion, an interesting but unconventional option was suggested. Repair cars follow the iron ore train and we could travel on one of the repair cars. It would cost nothing and was actually expected to be a lot more comfortable than the Iron Ore train itself. The only problem was to figure out when this repair car would ply from Ben Amera to Choum . Based on the latest information a midnight departure seemed likely and so we set our alarms and went to bed early. A little before midnight S trekked to the train station and found out that it was likely to be delayed and may depart only at 3:30 a.m. So we set the alarm again, took a brief nap and at 3:00 a.m., in total darkness, we trekked to the control building by the tracks. To our relief there was a repair car waiting on the tracks. In a few minutes we enjoyed the sight of the long Iron Ore train (with all the hoppers fully loaded) passing by enroute to Nouadhibou. Then we learned that while the track to Choum was free, the repair car would actually wait for the train going in the other direction to pass and actually follow it. This morning's train was expected to cross at 6:30 a.m. so we would not be leaving for Choum until then! So, we trekked back to the village for another couple of hours sleep before returning back to the signal station just after 6:00 a.m. A half hour later, the train from Nouadhibou passed by without stopping (unlike the previous day when it had stopped for us!) . 

Video of the Iron Ore train to Zouerat passing Ben Amera 
 
Video of the Iron Ore train passing the repair car
  
We boarded the repair car and took our seats trying to be as unobtrusive as possible. The car was operated by two men who had their head and face completely covered with cloth for protection from the sand. They looked like characters from a Science Fiction film accentuating our already surreal experience. We did not mind all the delays as this meant that we could enjoy the surrounding desert landscape in the morning light rather than travel in darkness. The driver paid little attention to us and stayed focused on his tasks. The only words he uttered were into the radio equipment to seek permission to leave and to coordinate the use of the tracks with other trains. The assistant had to periodically get out of the car to operate the levers that changed the track guidance. It was amazing to see the amount of manual effort required for this operation. At times the man had to use his full body weight on the level to get the tracks to move .

Video of repair car assistant manually aligning the railway tracks 
 
It took the car about 90 minutes to complete the 66km to Choum. We pulled behind the Iron Ore train whose last carriage was the passenger car disgorging passengers onto waiting 4x4 taxis. We found room at the rear of one (the driver was so keen on taking us that he evicted the previous occupants and moved them to the flatbed behind). It was a windy morning and the desert sand flew over the path in waves as we proceeded towards Atar, 120 km away.
 
Copies of fiche (photocopies of passport) were duly handed over at several checkpoints along the way. Visitors to Mauritania who plan to spend even a few days here are well advised to carry a big bunch, else you could spend a significant portion of your vacation waiting for the gendarmerie to copy your passport details into their ledger every time you enter or leave a city or village or take a highway. In fact when we jumped off the Iron Ore train in Ben Amera the previous night, we first had to register with the gendarmerie before we were allowed to stay in the village. Supposedly this is for our own safety, so they know how many tourists/foreigners are in a given area. But it is unclear what they are protecting us from.