It's hard to upgrade existing routes that far - the normal maximum for upgraded 'classic' railways will be <225kph, while new high-speed railways (like the Japa

It's hard to upgrade existing routes that far - the normal maximum for upgraded 'classic' railways will be <225kph, while new high-speed railways (like the Japanese shinkansen) can go over 300kph. That said, Europe already has quite an extensive high-speed network - especially in its Western parts. The French TGV, for instance, has comparable speeds to the Japanese high speed services, and there are similar (if less complete) networks in Spain, Germany, and other countries. So a high-speed network between major centres is entirely feasible and, in fact, currently being built.