Hi - retired TA (male) here :
I always recommend Arthur Ransome books, as they are interesting, well written, and impart a lot of information about children and life in the 1930s, without being too difficult or seeming like they are teaching history.
Swallows and Amazons was the first, of course, and is set in the Lake District but not in an exact location.
If he likes history or geography, then Coot Club is brilliant because all the locations are real, in the Norfolk Broads. The Ordnance Survey 2-1/2 inch map of the Broads shows all the places the children visit, and allowing for a few new roads and less railways, it has hardly changed. I found it fascinating to read the story while following the rivers and route on the map. The social history of the area is also covered: the children want to send a letter to friends in a nearby village, and say if they post it in the morning, it will arrive in the 'second post' the same afternoon! They buy provisions in a riverside shop, and all their purchases are carried down to their boat by the 'shop boy'.
Another book with a real location setting that can be found on maps is Watership Down. The housing development that destroyed the rabbits' home is on the outskirts of Newbury : www.lionking.org/~watership/
If he likes poetry, some of John Betjeman's collections might be a possibility, and I have done bits of Dylan Thomas' Under Milk Wood with young able readers.