I love Castleton in the Peak district. I was encouraged to go there through the Church and Scouts. You can sit in one of the nice cafes or browse through one of the shops on their High st. Or you can be more energetic and go for a walk in the beautiful countryside or go down one of the many Blue John mines dotted around the countryside.
Is a very interesting cave and requires a trip in a boat once you get down into it. I am not sure whether it is open all year, because heavy rain will effect when it can be used. It costs £11 for adults. Find out more here
Have you a story to tell about Speedwell cavern? It must have been horrific actually working down one of these mines and blasting out, with little regard to safety.
All the best