This is Puzzlewood, in the Forest of Dean - one of my favourite places. Tolkein visited here regularly and supposedly was inspired by this place to create Mirkwood and Fangorn Forest in Middle-earth. Walking round, it's easy to feel that link to the enchanted forests. The place feels ... old. It's very strange, in a delightful way.
Puzzlewood is a load of Roman open-cast mine workings, which are in an area of ancient woodland. You can see the stones of the mine in this picture, and everything is covered in moss as the area is very damp. Add in the spindly trees and you have a very unusual, very beautiful aesthetic.
I took a ton of pictures trying to capture the vibe, which are all in this gallery. It was an excellent day out.