I'm a little reluctant to book a train seat ahead of time because I don't know how long it will take to clear customs and get to Montparnasse (likely to ready around 1pm). However, I'm conscious it's peak vacation time then so would like advice on whether seats are likely to be booked out if I show up to purchase one.
Is it the TGV I would get from Montparnasse? I'm a little clueless with the train arrangements in Europe so any advice/suggestions will be gratefully received. Thanks