You maybe planning to traverse the continent on your railpass, but it’s always a good idea to know more about train reservation.

Railpasses cover 95% of all state-run trains in Europe, but don't cover reservation fees. For many trains (local, regional, interregional, EuroCity and InterCity trains, or Germany's speedy ICE), reservations are not necessary and not worth the trouble and expense unless you're traveling during a busy holiday period.

Reservations are required for any train marked with an "R" in the schedule (e.g., TGV and other high speed trains, Swiss scenic trains, long rides in Spain and Norway), and for couchettes and sleepers (see "Sleeping on Trains," below).

Seat reservations, which cost from $5 to $20, can be made as early as two months in advance (three for Thalys and other international routes from France, four for Eurostar), or up to a few hours in advance. Some "premier trains" charge railpass travelers a more expensive reservation fee called a Passholder Fare. All trains that require reservations can limit the number of seats available to passholders.

In high season, it is wise to reserve at least several days ahead (or as soon as you're ready to commit to a date and time) for night trains, weekends and holidays, routes with infrequent service, any train you cannot afford to miss, or if you need several seats together.

But if an advance reservation for a specific train will help you relax (and if you've already purchased your railpass), call Rail Europe at 800/438-7245 (from Canada, you can call Rail Europe at 800/361-7245). Reservations made in the U.S. cost a little more and are not changeable or refundable. A printed ticket will be shipped to you.