I suppose you are landing in Dusseldorf from the US. Before you leave you can get a Eurorail pass online, but you may/may not buy a ticket direct from German rail ( I could be wrong here). You can get a ticket at the railstation in Dusseldorf when you get there. The Germain trains are great. One reason I mention that you may be able to order rail tickets I tried to find a method to get from St. Petersburg Russia to Findland when I was there and I think I could have reserved a ticket online if I had wanted to take a 14 hour train ride. If you are going soon make sure you take a coat with you to Dusseldorf it is starting to cool down this time of year and can get pretty cold.
about 4 hours probaly 5
According to raileurope.com a train from Paris to Madrid takes approximately 13 hours.
About 4 Hours.
clear 3 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.
About 3 hours
1 hour
7 to 8 hours.
This depends on if you take a bullet train or regular train. Regular train is actually about 13 hours. 5 hours
You take the train from Paris-Saint-Lazare
It depends how much money you have .
== == Less than an hour on the RER train.