Inspiration: Dol Baran was a hill in Rohan.
Dol Baran lay between Isengard and the Gap of Rohan, at the southernmost foot of the Misty Mountains. It was covered with heather. Dol Baran was the place where Rohirrim had made a camp at which Pippin looked into the Palantír of Orthanc (a different location than in the third film), and was also where a Nazgûl, atop a Fellbeast, was seen flying.
- The Atlas of Middle-earth, Regional Maps, “The Misty Mountains”
- 2.0 2.1 The Lord of the Rings, The Two Towers, Book Three, Chapter XI: “The Palantír”
- The Lord of the Rings, Appendix B: The Tale of Years (Chronology of the Westlands), “The Great Years”
- The Complete Guide to Middle-earth