I painted this up for my father as a present. It's my first diorama, but I'm pleased with the results!

Inside, I placed a flickering tea light for some ambiance.
The cave was built with cork board, hot glue, and milliput (superfine white and regular).
The plinth was a slice of wood from the art supply store, stained and coated in polyurethane.

Individual close up views of completed miniatures available in WIP link, if interested.