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I'm going to be traveling to Germany from the US, and on the flight back that is preferable for other reasons, we'll be going Nuremberg->Frankfurt, then have 1.5 hours, then -> Chicago.
Is that long enough for that stage? I'm not an experienced international traveller (I've never been on that side of the Atlantic, for example), and I'm somewhat concerned about what might happen if my puddle-jumper gets delayed (as I'm sure they do from time to time).
(Unfortunately, the other option is a 5 hour layover; that seems to me to be just short enough that we can't really go see anything (not that FRA has much to see from what I've read) and long enough my two toddlers will dislike it if we stay at the airport.)