Frankfurt layover...Mainz?

I think that it makes little difference where you choose to stay. Most places will be closed and only open after you're at the airport. I would select a place based on price. Note that Frankfurt has trade shows that can easily triple the price of rooms and make them unavailable, so you don't want to stay there if that's the case. For another larger city, you also have Wiesbaden which is across the Rhine from Mainz.

Thanks for your help. Do you have any Frankfurt hotel recommendations? Obviously since we're only there for the night we don't need anything fancy, just in a good walking area and close to the sights we can see at night.

hey, so i am coming from an area close to mainz and if you wanna visit mainz that could be nice too.. if the wheater is nice you could check out Mainzstrand (http://www.mainzstrand.de/) where you can sit outside directly at the river. or you could check out the local brewery (http://www.eisgrub.de/#Beer). they also have a hostel and that might be a good option (https://www.hihostels.com/hostels/mainz). you can see the cathedral and walk along the river in mainz and the view over the city is pretty....
otherwise if you are in frankfurt you could check in here overnight: http://www.frankfurt-hostel.com/ and have a look at the römer and the old city part and walk along the river for a bit too...
not sure about the amount of lagguage you have otherwise you could also just sleep in mainz, check out the city in the evening and then head to frankfurt in the morning, look around there and then go back to the airport... that might work too....
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