I like this line. It's got a nice ring to it, and also it reminds me of my first impression of Hogwarts, before it's actually described in the book. I pretty much imagined a whole lot of tables outside on a veranda type thing with adults teaching the kids your basic magic tricks (top hats, frogs, rabbits etc). I'm so glad Harry didn't go there.
However, I apparently didn't pay much attention to the description of Hogwarts when it was given to me, particularly the Entrance Hall.
'A magnificent marble staircase facing them led to the upper floors.' Unfortunately, my Hogwarts is built with a completely different layout to the one in the book, because I imagined the marble staircase to the right. It's made a mess of a lot of scenes in the book for me, and I was puzzled when the movies came out about why they put the staircase in front of the entrance, but there you go. That's one thing I love about reading: everyone imagines it differently. Some more correctly than others, perhaps, but that's a matter of opinion.