Frankfurt as a Stop-Over

You found a cheap flight with a stop over in Frankfurt am Main, Germany? Great, use the undesirable pause to visit a few places of interest.

2 Hours Stop-Over

Stay in the airport!

4 Hours Stop-Over

Pray with a minyan!

Frankfurt has a daily Shacharit and Mincha/Maariv minyan, located in the Westend-Synagogue (inside the Shtible). For time please see here.

Visit a Kever Tzaddikim!

In Frankfurt are buried quite a few great Tzaddikim. If you have a chance make sure to visit them.
Very old cemetery Batton Street: Rabbi Natan Adler, Rabbi Pinchas Halevi Horowitz, Rabbi Jakob Joshua Falk - (Penei Yehoshua), Mayer Amschel Rothschild

Old cemetery Rat Beil Street: Stoliner Rebbe, Rabbi Shimshon Rafael Hirsch

8 Hours Stop-Over

You can tour Michelstadt or Worms and Speyer. I dont know if you can make everything in 8 hours, the best is you call one of the taxi drivers for more details.