Underground dwelling o/t Tuatha d Danaan or- "Children f Danu", mythological mother goddess o/t Irish Celts. Fairy folk like Leprechauns inhabit these places, particularly under th burial aka fairy mounds
This scenic location is Puzzlewood, a popular outdoor tourist destination in Gloucestershire, England. It’s said to have inspired J.R.R. Tolkien’s conception of the Old Forest, Mirkwood, Lothlorien, and other places in his Middle Earth.