INFORMATION:

What is good about searching out any wartime places are looking for clues.

One: two entrances.

Two: concrete/ tarmac road surface that has deteriorated in places where it normally, would not be. (As here in woodland).

Three: corrugated iron lying around (usually rusted).
Any way the list goes on - another is a caravan site. Nearly always an ex-camp. The caravans are usually placed on hut bases.