To take advantage of these prices you will need to prove you are not a business traveller, on the way to stansted airport, so you will need to provide either your flight numbers or yr holiday booking reference. I don't think you will need to provide this when you arrive at caledonian-road station but you may be asked to give them on yr travels from caledonian-road station to the airport.
Going to the airport by train is great, you can take a nap, read (even at night), play travel scrabble, or just gaze out of the window... The other restriction to buying these inexpensive tickets from the station to stansted airport is that there must be at least two adults travelling together. But another great benefit is that children go free. All children under 5 go free, and then one kidover five but under sixteen per adult travelling by train to stansted airport.
make sure you leave plenty of time to get to the airport early enough to eat, shop and so on, so check the times of trains from the station before you go. If you have time to kill at the airport you can always read a book or play a game again! As you have bought yr train ticket in advance, you don't need to fret about the opening times of the station.
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