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You could send it by UPS, £53 for 190x5x5 parc elEurostar seems like a dead loss. Now RyanAir has max dimensions for checked baggage as 810 x 1190 x 1190. A bit of pythagoras and I work out corner to diagonally opposite corner is 1860. So I could go that way. Which is cheaper than Eurostar. But what do I make this box out of?