Date unknown. I think it was between books 3 and 4.
We were invited to a [wiki:Larp LARP] based on [wiki:Harry_potter Harry Potter].
Here you can see the castle (used to entertain the children). In the foreground is Hagrid, played by ["Calin"], and various other characters. The sinister-looking woman in red and black was the new Defense against the Dark Arts teacher. She didn't last till next term.
Hagrid was the Care of Magical Creatures instructor, and one of his abilities was a stomach of iron. He could remove any item from the game by eating it. Here you can see Hagrid removing a sandwich from play. Sadly, one of his creatures got a little too much sun, and had to be carefully revived.
["Paw"] got to play [wiki:Arther_Weasley Arthur Weasley], who was perpetually out of money, and on the brink of getting in trouble for his unauthorized use of magical artifacts. Not that he meant any harm by it.
And here we have ["Shelly"], who played Veronica Verdicious, a rich Slytherin girl with a talent for cheating and demon summoning. Both in the same day, no less.
The librarian looked the part rather well, and though Dumbledore didn't have a beard, he certainly had the right sparkle in his eyes. [wiki:Argus_Filch Filch] didn't really look the part, but he played it well. And it was in the rules that things looked the way they were supposed to. If something had a sticker on it that had a description (like this nice flowerpot Sarah Smythe was carrying), then that's what it looked like.
Here's a shot of several members of the Hogwarts staff hanging out in the shade provided by a very nice tarp.
Overall, the game was fascinating. Kind of like playing a [wiki:Kings_Quest King's Quest] (or any other [wiki:Sierra_On-Line Sierra]) game. Every character had goals and motives, and playing was all about finding the right person to help you solve your problem. And then convincing them to help you.
The [wiki:Gamemaster GM]s (or storytellers, if you prefer) had their hands full, but they did a great job. Look how busy they look. We were all quite enthralled whenever they spoke.