Some people believe that these trains could be the future of transportation. They are quiet and do not need electricity or diesel fuel for power. Since maglev trains do not need engines, there is no pollution. Moreover, meglev trians have achieved a top speed of 501 km/h. But others disagree. one very big disadvantage of maglev trains is that operate in france, japan and Germany, maglev trains need their own special tracks. It would be very expensive to build an entire new track system that could only be used for one type of train. This means building over 50,000 km of tracks in many European countries.