It depends on from where you set off.
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.
About an hour
8hrs 30mins
The train ride from London to Paris typically takes around 2 hours and 15 minutes.
About 4 Hours.
The Eurostar train journey from London to Paris takes approximately 2 hours and 15 minutes.
On an express train (TVG), a little over 6 hours.
7 to 8 hours.
About 3 hours
1 hour
2 days