Even if there isn't the problem of different track types, there are bound to be many major disagreements between the different countries it passes through, and possibly border checks etc. It's kind of a headache, especially if it goes outside the EU too.
I agree it is easier because the US also uses one track type which can be an issue with trains moving internationally.
Even if there isn't the problem of different track types, there are bound to be many major disagreements between the different countries it passes through, and possibly border checks etc. It's kind of a headache, especially if it goes outside the EU too.