To take advantage of these prices you will need to prove you are not a business traveller, on the way to edinburgh airport, so you will need to give either yr flight details or your 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 yr journey from the station to the airport.
Going to the airport by train is great, you can sleep, read (even at night), play travel scrabble, or just stare out of the window... The other restriction to buying these inexpensive train tickets from the station to the airport is that there must be at least two adults travelling together. But another great advantage is that children go free. All children under five go free, and then one kidover five but under 16 per grown up travelling by train to the airport.
be sure to leave enough time to get to edinburgh airport early enough to eat, shop etc, so check the times of trains from the station before you go. If you end up with spare time at edinburgh 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 middlesbrough station.
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