Here is a concise summary of the text:
**Title:** The 2.5km Long Sahara Train: Transporting Iron Ore Across Mauritania
**Key Points:**
1. **Journey Details**:
* 704km journey from Zouerate (Mauritania) to Nouadhibou
* 20-hour trip through the Sahara desert with temperatures up to 48°C
2. **Train Specifications**:
* Up to 2.5km long, with 200-210 freight cars, 1-2 passenger cars, and 10 assorted cars
* Pulls approximately 17,640 tons of cargo
* Utilizes 2-4 diesel-electric locomotives (EMD SD70ACS) with 3300-4500hp each
3. **Desert-Ready Features**:
* Special air filters, sealed compartments, and positive pressure body to reduce sand ingress
* Radiator design and dynamic braking system for efficient cooling
4. **Efficiency Comparison: Train vs. Truck**:
* Trains are approximately 3.7 times more efficient than trucks (190km/ton/liter vs. 51.6km/ton/liter)
* Lower power per ton ratio, reduced maintenance costs, and lesser wind drag
5. **Additional Context**:
* Railway built in 1960, financed by international partnership, and purchased by Mauritania in 1974
* Trains transport 11% of Mauritania's GDP and 43% of exports (2020 data)
* Intermodal transport highlighted as key to optimizing efficiency and costs.
Here are the key facts extracted from the text, numbered and in short sentences:
**Train and Route**
1. The train travels 704 km through the Sahara desert in Mauritania.
2. The journey takes approximately 20 hours.
3. The train's origin is the Zouerate region (iron ore mines).
4. The train's destination is the port in Nouadhibou city.
**Train Specifications**
5. The train can reach up to 2.5 kilometers in length.
6. It can pull over 17,000 tons of cargo.
7. The train typically consists of 200-210 freight cars, 1-2 passenger cars, and 10 assorted cars.
**Locomotive**
8. The locomotives used are diesel-electric.
9. Each locomotive has 3,300 hp (or 4,500 hp in some cases).
10. Up to 4 locomotives can be used to pull the train.
11. The locomotives are connected by electrical control cables and pneumatic brake hoses.
**Model and Modifications**
12. The locomotive model is EMD SD70ACS, designed for desert operations.
13. Modifications include special air filters, a downward-facing radiator, and protected fan blades.
**Railway and Operations**
14. The railway was constructed starting in 1960, after Mauritania's independence from France.
15. The project was financed by an international partnership (France, UK, Germany, Italy, and 5% by Mauritania).
16. The railway was fully operational by 1963 and was fully purchased by the Mauritanian government by 1974.
17. Six trains run daily on the railway (3 loaded, 3 empty).
18. The railway has only one track, with 9 sidings for passing trains.
19. There are 6 maintenance bases along the railway.
**Passenger Transport**
20. 2-3 passenger cars are connected to the train once a day.
21. Passenger cars often are cargo cars adapted with small windows.
22. These cars are usually overcrowded (exceeding the recommended 25 people per car).
**Efficiency Comparison (Train vs. Truck)**
23. A train transports 1 ton approximately 190 km per liter of diesel.
24. A truck transports 1 ton approximately 51.6 km per liter of diesel.
25. The train is around 3.7 times more efficient than a truck for this route.
26. The power per ton of load ratio is 0.5 hp/ton for the train and 3 hp/ton for a standard truck.