The term 'RANGE IN HEIDI' is a reference to the classic children's novel Heidi, written by Johanna Spyri in 1880. The crossword solution for this term is ALPS, which is a mountain range located in Europe that stretches from Austria and Slovenia in the east, through Italy, Switzerland, Liechtenstein, and Germany, to France in the west. The ALPS are the highest and most extensive mountain range in Europe, and they are featured prominently in the novel Heidi.