GNER has recently adopted airline-style pricing, making fares even more affordable if you're only travelling one-way, the cheapest Advance single ticket from London to Edinburgh being £12.50 in standard class, half the bmi fare. A First Class Advance single is £29.50 making £59 the lowest-priced return fare in First if you can book well enough in advance.

I've done plenty of day trips from LON-EDI on GNER and even though flying is roughly an hour quicker than rail, the extra time on the train is spent more productively. I always enjoy GNER's full English Breakfast on the way up and a three-course dinner on the way home. The last time I flew from London to Scotland was more than 10 years ago! For me, I'll always prefer the train*.

*Excludes Virgin Trains