I don't know why I'm having so much trouble figuring this out, but the DB site confuses me. What is the best way to take a fast train from the Frankfurt Airport (coming from U.S.) to Luxembourg, going to the Kirchberg Conference Center? The DB site does not say which train is the one at the airport. It's for a business traveler, so I'm looking for the fastest and most convenient method of travel, not necessarily the cheapest. I know Luxair flies, but flight times don't work. Thank you!