Last night, I went to the theatre to see the first part of Harry Potter & the Cursed Child. Tonight, I’m going to see the conclusion. (Yes, I’m 36 years old, so what, bugger off.)

There are signs all over the theatre, asking the audience to “keep the secrets” – not to give away details of the plot, and so spoil it for those who haven’t seen it yet. And I have no desire to spend my weekend fighting off an army of angry Potter fans, so I’m not going to say anything except this one thing:

At one point, you can see a map showing the route of the Hogwarts Express.

There are probably some other things that happen in that scene, but I have no idea what they are because I was so busy studying the map.

It’s not a tube-style line map, to be clear. (I mean, why bother? There are only two stops.) Instead, it’s a map of the British Isles with the train’s route superimposed upon it.

From memory, the route looks a bit like this:

The Hogwarts Express starts at Kings Cross (obviously). But instead of following the East Coast Main Line, through Peterborough and Lincolnshire, it runs slightly to the east, before making a sharp turn west at the Wash. It then heads north again, presumably following the main line to Edinburgh and across the Forth Bridge, then does a weird u-turn-y bit in western Scotland.

It has more twists and turns in it than you’d expect, is my main point here. This is probably because what I’m reporting on is a theatrical prop rather than a map of an actual railway line, but nonetheless, it does suggest the “Express” part of the name may be a bit of a misnomer.

One other thing about the map that might be worth noting: although it’s a screengrab which I’ve scribbled on, a quick search of Google Maps does actually reveal the location Hogwarts. It’s here:

That’s not far from Rannoch Moor, one of the locations used in the Harry Potter firms. There are some pictures added by users, too.

And it’s had excellent reviews:

Best we can tell, this is not the location of the Pottermore offices, let alone an actual magic castle. Instead it seems merely to be an easter egg placed there by Google.

I wouldn’t bother going there in the hope of actually finding something more interesting than a loch, is my point here. But if lochs are you thing, then be my guest.

Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.

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