In Mauritania, only one train to ride exists: It is nicknamed the Iron Train. It stops once for five minutes in Choum on its daily 437-mile journey from Zouerat in central Mauritania to Nouadhibou on the coast. Its main purpose is to transport iron ore, 22,000 tons mined in Zouerat daily and poured into 220 iron hoppers linked together to make a 1.5-mile-long train. Passengers can stow away for free in the hoppers or they can pay about $3 to sit on benches inside two passenger cars. The journey can take anywhere from 16-21 hours depending on the weight of the train.