Originally Posted by
saint_em
We'd naturally assumed that Frankfurt would be best in terms of getting to/from the airport, but Mainz sounds like it will fit the bill.
Ironically, the same S-Bahn line takes you to both central Frankfurt and also to Mainz - it all depends which direction you take (the line in the direction of Mainz continues on to Wiesbaden, another nice town to visit, possibly on a future trip).