Roll up your sleeves! A choice here, but which one to go for? A torch may be useful for this one, unless of course you like sticking your hand blindly into dark holes...
A short series of caches by EloiseTurner and the Teabandit placed in a lovely little wood (and its approach) north of Amersham. The caches are largely straightforward and all in film containers. Some will require you a detour from a single route. Enjoy!