This is a distance of roughly 625 miles and we are going to assume that the speed does not include the time penalty of Spain having a different Rail Gauge than France.
At 890 miles of rail you can get New York to Chicago which would be the ideal first route, but what can you get with 625 miles that makes more since than Columbus?
Well at that distance you can get Raleigh-DC-Philadelphia-NYC- Boston
With intermediate stops in Richmond, Baltimore, New Haven, and Providence
That is a route that is not only good, but has potential to be one of the most used rail lines in the world if it were at high speeds and a cheap price