To take advantage of these prices you will need to prove you are a leisure traveller, en route to luton airport, so you will need to provide either yr flight details or your holiday booking reference. I don't think you will need to provide this when you arrive at high-wycombe station but you may be asked to provide them on yr journey from high-wycombe station to luton airport.
Going to luton airport on the train is great, you can sleep, read a book (even at night), play travel scrabble, or just gaze out of the window... The other restriction to buying these cheap tickets from high-wycombe station to luton airport is that there must be at least two adults travelling together. But another great advantage is that kids go free. All children under five go free, and then one child over 5 but under 16 per adult travelling on the train to luton airport.
be sure to leave enough time to get to luton airport early enough to eat, shop etc, so check the times of trains from high-wycombe station before you go. If you end up with time to kill at luton airport you can always read or play a game again! As you have bought your train ticket in advance, you don't need to worry about the opening hours of high-wycombe station.
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