22h10 including night train (sleeperettes) between Barcelona and Milan.
3 days and 2 hours
The quickest train from Brussels to Paris usually takes not very long at all. The quickest train from Brussels to Paris usually takes about one hour and fifteen minutes.
According to raileurope.com a train from Paris to Madrid takes approximately 13 hours.
lyon - vienna
7 housr
It takes 4 hours.
It takes about 1 day and 3 hours to get from London to Rome by train.
The train from Zürich to Vienna is not a TGV, it is a normal train with top speed 200Kph. But for most of route it does less than that. It takes about 7 hours from Zürich to Vienna. But the route is very picturesque, as it goes lengthways through the Alps.
The distance between Paris and Bari in Italy takes about 15 hours by trains.
5
500 km
The ca. 180-km-train ride takes pretty exactly 2:30 - due to the train having to go through a very beautiful mountain range, the Semmering...
The TGV, also known as Train a Grande Vitesse, travels three times a day between Paris and Milan. The entire trip takes about 7 hours.