Open access, free of charge.
In King's Cross train station.
We challenge anyone who read the Harry Potter books as a kid to wander past the real-life tribute to the Hogwarts Express portal and not be immediately transported back in time to the moment when you first met Hermione and Ron, and a whole new world started to open up before your eyes. The luggage trolley, found next to Platform 9 at Kings Cross train station (no coincidence), is a wonderful reminder of the power of books to whisk us away on a journey that, like Harry's first train to the school of magic, seems at the same time so improbable and so wholly consuming.
There's usually a helpful staff member who (in true British style) controls the roped queue, and will also happily hold a flailing scarf for the obligatory photo. Importantly, and potentially significantly, you choose a house scarf. Time to decide if you really are the Gryffindor you've always wanted to be.
There's a shop just around the corner where you can pick up all the supplies you'll need for the term ahead.