For once a childhood favourite doesn't disappoint on a re-read several decades later. It's a lost world that's depicted, in which young adolescents can go off on their own all day, and of course they get into a wild (but very believable) adventure. All the characters are memorable and drawn with a good deal of humour, and while the set-up for the denouement seems a little contrived to my older self, the writing moves at such a pace that it hardly matters. The moors of the Peak District are full of atmosphere - as is the cheery setting of the Youth Hostel they stay at. And the treasure everyone is searching for is entirely worthy of being the subject of a novel.