Try Enid Blighton's... 5 go mad in Dorset!
Probably one of the great pieces of writing ever produced...impelling in fact!
Not only does it give you a great insight into the history of Dorset and surrounding areas....but it also keeps you on the edge of your seat with all the twists and double twist it has...till the very last page has been read.
I just can't praise it enough!