Airport

Probably Frankfurt Hahn (which is nowhere near Frankfurt) is closest in Germany, but coming from the North America, Frankfurt am Main is the probably easiest.

Go to Rick's page about the tour: http://www.ricksteves.com/tours/germany-austria-switzerland/germany-austria-switzerland-tour. click the "Pre-Tour" tab, and you'll see the following:

<>Transportation

Most tour members arrive a day or two before the tour begins — and those who don't, wish they had. This allows you ample time to get over jet lag and make the most of the first few days of the tour.

There is more than one way to get to and from your tour. We recommend talking to your travel agent about "open jaw" airline tickets (flying into and out of different cities).

Frankfurt International Airport (Frankfurt am Main) is the main airport in Germany — 110 miles from Trier. If you fly into Frankfurt am Main, you will then need to take a train from the airport to Trier, a 3-4 hour journey. Frankfurt Hahn airport is a smaller airport located just 40 miles from Trier, but it is only serviced by low-cost airlines, including RyanAir and Wizz Air. It takes an hour to go by bus from this airport to Trier. See http://www.flibco.com/hahn/morbach.htm for more information.
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Prior to your tour departure, you will receive detailed directions on how to get from the airport to your first tour hotel, as well as contact information for your first and last hotels in case you wish to book pre- or post-tour hotel accommodations.

If you need more information about additional European travel or for specific questions about your tour, contact the Tour Department at 425/608-4217 or email tour@ricksteves.com.<

I'll just add that if you're flying from the US, Frankfurt am Main has by far the most service of any airport close to Trier. There is also some nonstop service to Cologne-Bonn Airport. If you have to change planes anyway, look into Luxemburg, Saarbruecken, or Frankfurt-Hahn.

Suzanne,

As the RS tour information indicates, Frankfurt is probably the best bet. FRA is well organized and there are two rail stations right at the airport. Travel times from FRA to Trier are as short as 2H:40M with one or two changes, depending on the arrival time of your flight. You'll probably be using the FRA Fernbahnhof station, and there's a ticket office there as well.

You can check the details and times using the bahn.de website.

If you can get a direct flight from the States, Luxembourg is well worth looking into as well as the "real" Frankfurt airport. The disadvantage is that there's no railway station at the airport, so you need to get a bus or taxi to the railway station in the city centre, but the train journey will be shorter than from Frankfurt.

Please give our tour department a call with any tour related questions at (425) 771-8303 ext. 217. We recommend flying into Frankfurt airport and training over to Trier to meet the group. See train schedules at www.bahn.com and other info at www.ricksteves.com/rail.