Much of what I know today about the history and archaeology of North Yorkshire comes from Raymond H Hayes. It was a true joy to see one of his field maps on display in the Ryedale Folk Museum.
Update. I’ve just been reading some recollections by Raymond Hayes, he writes of Mr Crosland giving him his set of 6″ OS maps on which he had marked sites and finds. Mr Crosland had a small museum at Hutton Le Hole which later became the Ryedale Folk Museum so I guess the map may be one of Mr Crosland’s. Hayes writes that the maps were extremely useful when he became OS Correspondent at the invitation of Charles Phillips.