Forget this Prague-idea.
(iīm a truck driver by profession and i know the german Autobahn around...) Since i live near Heidelberg (just 15 mins away from HD

)
Itīs similar to Frankfurt by distance to PRG. And i wouldnīt even consider a 24 hr trip to Prague (donīt forget that gasolineprices in Europe are significantly higher than in the U.S.!!!)
It makes no sense at all for a 24hr trip.
If you donīt want to spend the evening/night at Frankfurt there are sooooo many doable choices!
e.g.: Heidelberg is just a 50mins-1hr drive from FRA; Mainz as mentioned is also nice (and just 30 mins to go there from FRA)
Thank you. I just spent three days in Heidelberg last month on business, and thoroughly enjoyed myself. Stayed in
Die Hirschgasse. Was a lovely city and lovely hotel. ^