To take benefit of the best prices you will need to prove you are a leisure traveller, en route to gatwick airport, so you will need to provide either yr flight numbers or yr holiday booking reference. I don't think you will need to provide this when you arrive at the station but you may be asked to give them on your journey from the station to the airport.
Going to the airport on the train is great, you can take a nap, 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 bracknell station to gatwick airport is that there must be at least two grown ups travelling together. But another great advantage is that children go free. All children under 5 go free, and then one child over five but under sixteen per adult travelling on the train to gatwick airport.
be sure to leave enough time to get to gatwick airport early enough to eat, shop etc, so check the times of trains from bracknell station before you go. If you have spare time at gatwick airport you can always read a book or play travel scrabble again! As you have bought yr train ticket in advance, you don't need to fret about the opening hours of the station.
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