IT’S 20 YEARS SINCE HARRY POTTER AND THE PHILOSOPHER’S STONE WAS FIRST PUBLISHED. ELLA WALKER FLIES OFF ON A BEWITCHING TOUR OF THE POTTER FILMING LOCATIONS

the magic to be constantly reminded of the distinct, graspable line between fiction and reality.

Look up from Professor Snape’s robes, which hang upsettingly motionless beside Professor Dumbledore’s in the overwhelming expanse of the Great Hall, and an exposed ribcage of a ceiling, spiked through with scaffolding, gapes wide where Rowling’s enchanted sky ought to be.

A series of beautiful architectural blueprints and model sets, including an intricate matchstick dummy of the owlery, where ittybitty illustrated owls sit, ready and waiting to deliver wizarding mail, reveal the films’ skeletal frames, while the hundreds of peeling wand boxes that buttress the windows of Ollivanders store, we’re told, were each painstakingly handlabelled by set dressers (not wandmakers).

At Alnwick Castle, an hour’s drive north of Newcastle – its bulky Norman walls the scuffed goldblack of an old pound coin – the line between living the magic and just looking, is brilliantly disguised.

Instead of obeying ‘Keep off the grass’ signs, budding Quidditch players (ahem, me included) run amok on the frog-green lawns (broomstick training sessions are free, but it’s wise to book in advance), mimicking Harry’s fateful first flying lesson with Madam Hooch, which was filmed in the castle’s outer bailey.

The blocky inner bailey is also where, in The Chamber Of Secrets, Harry and Ron crash Mr Weasley’s cerulean flight-enabled Ford Anglia.

There’s no stately stuffiness at Alnwick, partly because it’s still a home, not a monument. Owner Ralph Percy, 12th Duke of Northumberland, lives here with his family (October to March, for the