6 hour layover in Frankfurt

3 of us are travelling to Italy and will have a 6-hour layover in Frankfurt -- during the daytime. Is there anything that we could possibly do during that time other than hang out at the airport?

You could travel by S-Bahn (station in basemen of Terminal 1) to the stop Hauptwache. Which in the mid of the city centre and next to the main shopping street, the Zeil. Travel time is 15 minutes. Buy a mini group day ticket for EUR 13,70 (cheaper than single tickets).

city tour leaflet
Hauptwache is #18 on the map.

First of all, you need to be sure WHICH Frankfurt airport you are at. There is the big, internationally known FRA airport, also called Frankfurt am Main, and then there is Frankfurt Hahn (don't know the IATA code for that) which is used by some of the cheapo European airlines. Frankfurt Hahn is actually something like 2.5 hours away from the real Frankfurt airport. The use of the name Frankfurt Hahn dates back to the post WWII era when this airport began to be used and they deliberately misnamed it Frankfurt Hahn because nobody outside of Germany ever heard of Hahn, but many foreigners had heard of Frankfurt. Very confusing, huh?

Assuming your layover is in the real FRA airport, you can go by S-Bahn into the city. If I remember correctly, I think Haputwache is the name for what should be called the Hauptbanhoff. It's the main train station. The main train station is centrally located. Frankfurt is a rather unremarkable city, in my opinion worth visiting ONLY if you are in the area. Anyone who goes there specifically to visit Frankfurt will surely be disappointed. The Jewish Museum is surprisingly good. I went there only because it was literally the only museum open on some obscure May holiday a couple of years ago. Honestly, I probably wouldn't have gone otherwise, but I was shocked at how good and interesting it was. Frankfurt has a smallish cinema museum that I thought was interesting. Their main classical art gallery was a gigantic disappointment to me, having no paintings I was even remotely interested in. At least when I was there, it seemed that all of the good stuff was out on loan to other museums. There were much much better art museums in Cologne and Stuttgart.

Thanks for the info. We arrive at FRA so we should be able to get into the city instead of being bored at the airport.

An alternative to Frankfurt is to take the S-bahn in the other direction from the airport to either Mainz or Wiesbaden. They are all distinctly different and any of them would make a good destination for a short stop. Maybe google for pictures of the three places in order to make an appropriate choice.

If you are traveling to the US on the way back, be aware of a possibly almost hour extra security check besides the normal one.

Go to one of the big FKK clubs.