We like to jet-lag a couple of days before starting tours. Should we fly directly from U.S.A to Frankfurt or is there a more relaxing place to jet lag in Germany a couple of days before going to Frankfurt? Nothing hectic though.
Close to Frankfurt you will find wine region Rheingau with beautiful places such as Eltville, Kloster Eberbach or Oestrich-Winkel. Very relaxed there and good to explore Upper Mid Rhine Valley by a day cruise on river Rhine.
Also mountain range Taunus western of Frankfurt with renowned spa town Königstein or Kronberg are a good alternative.
A couple of years ago, we flew into Frankfurt, ultimate destination the Allgäu, but we wanted to somewhat get over jetlag before a long train trip, so we went down to St Goar for two nights, took a Rhein cruise after the first night. That also allowed us to use a Sparpreis ticket to Bavaria without worrying about a late arrival.